<?xml version="1.0" encoding="utf-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" version="2.0"><channel><title>杨永康</title><link>http://www.yyk8.cn/</link><description>记录学习、工作、生活点滴</description><item><title>图解 | 你管这破玩意儿叫TCP？</title><link>http://www.yyk8.cn/?id=52</link><description>&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;你是一台电脑，你的名字叫 A&lt;/span&gt;&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 19px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957830367294.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;经过&lt;a href=&quot;http://www.yyk8.cn/?id=51&quot; target=&quot;_blank&quot;&gt;《图解 | 你管这破玩意儿叫网络？》&lt;/a&gt;这篇文章中的一番折腾，只要你知道另一位伙伴 B 的 IP 地址，且你们之间的网络是通的，无论多远，你都可以将一个数据包发送给你的伙伴 B&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957830110340.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: 0px;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;这就是物理层、数据链路层、网络层这三层所做的事情。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;站在第四层的你，就可以不要脸地利用下三层所做的铺垫，随心所欲地发送数据，而不必担心找不到对方了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755958607232820.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;虽然你此时还什么都没干，但你还是给自己这一层起了个响亮的名字，叫做&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;传输层&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;你本以为自己所在的第四层万事大吉，啥事没有，但很快问题就接踵而至。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #FF0000;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;问题来了&lt;/span&gt;&lt;/strong&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;前三层协议只能把数据包从一个主机搬到另外一台主机，但是，到了目的地以后，数据包具体交给哪个&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;程序&lt;/strong&gt;（进程）呢？&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img width=&quot;800&quot; src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957831568209.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;所以，你需要把通信的进程区分开来，于是就给每个进程分配一个数字编号，你给它起了一个响亮的名字：&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;端口号&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957831331309.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;然后你在要发送的数据包上，增加了传输层的头部，&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;源端口号&lt;/strong&gt;与&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;目标端口号&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957832580749.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;OK，这样你将原本主机到主机的通信，升级为了&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;进程和进程之间的通信&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;你没有意识到，你不知不觉实现了&amp;nbsp;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;UDP 协议&lt;/strong&gt;！&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #888888; font-size: 15px;&quot;&gt;（当然 UDP 协议中不光有源端口和目标端口，还有数据包长度和校验值，我们暂且略过）&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;就这样，你用 UDP 协议无忧无虑地同 B 进行着通信，一直没发生什么问题。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957832841619.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;但很快，你发现事情变得非常复杂......&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #FF0000;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;丢包问题&lt;/span&gt;&lt;/strong&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;由于网络的不可靠，数据包可能在半路丢失，而 A 和 B 却无法察觉。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957832511742.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;对于丢包问题，只要解决两个事就好了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;第一个，A 怎么知道包丢了？&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;　　答案：让 B 告诉 A&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;第二个，丢了的包怎么办？&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;　　答案：重传&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;于是你设计了如下方案，A 每发一个包，都必须收到来自 B 的&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;确认&lt;/strong&gt;（ACK），再发下一个，否则在一定时间内没有收到确认，就&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;重传&lt;/strong&gt;这个包。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957833312448.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;你管它叫&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;停止等待协议&lt;/strong&gt;。只要按照这个协议来，虽然 A 无法保证 B 一定能收到包，但 A 能够确认 B 是否收到了包，收不到就重试，尽最大努力让这个通信过程变得可靠，于是你们现在的通信过程又有了一个新的特征，&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;可靠交付&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p data-mid=&quot;&quot; data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: PingFangSC-Medium, &amp;quot;PingFang SC&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; font-weight: bold; letter-spacing: 0.015em; line-height: 22px; word-break: break-word; text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); color: rgb(131, 173, 155); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #FF0000;&quot;&gt;效率问题&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;停止等待虽然能解决问题，但是效率太低了，A 原本可以在发完第一个数据包之后立刻开始发第二个数据包，但由于停止等待协议，A 必须等数据包到达了 B ，且 B 的 ACK 包又回到了 A，才可以继续发第二个数据包，这效率慢得可不是一点两点。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;于是你对这个过程进行了改进，采用&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;流水线&lt;/strong&gt;的方式，不再傻傻地等。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957833922638.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: 0px;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #FF0000;&quot;&gt;顺序问题&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;但是网路是复杂的、不可靠的。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;有的时候 A 发出去的数据包，分别走了不同的路由到达 B，可能无法保证和发送数据包时一样的顺序。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957833704696.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: 0px;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;在流水线中有多个数据包和ACK包在&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;乱序流动&lt;/strong&gt;，他们之间对应关系就乱掉了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;难道还回到停止等待协议？A 每收到一个包的确认（ACK）再发下一个包，那就根本不存在顺序问题。应该有更好的办法！&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;A 在发送的数据包中增加一个&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;序号&lt;/strong&gt;（seq），同时 B 要在 ACK 包上增加一个&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;确认号&lt;/strong&gt;（ack），这样不但解决了停止等待协议的效率问题，也通过这样标序号的方式解决了顺序问题。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957833464023.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;而 B 这个确认号意味深长：比如 B 发了一个确认号为 ack = 3，它不仅仅表示 A 发送的序号为 2 的包收到了，还表示 2 之前的数据包都收到了。这种方式叫&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;累计确认&lt;/strong&gt;或&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;累计应答&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957833418046.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; font-size: 15px; color: #888888;&quot;&gt;注意，实际上 ack 的号是收到的最后一个数据包的序号 seq + 1，也就是告诉对方下一个应该发的序号是多少。但图中为了便于理解，ack 就表示收到的那个序号，不必纠结。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #FF0000;&quot;&gt;流量问题&lt;/span&gt;&lt;/strong&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; font-size: 15px; color: #000000;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; font-size: 16px; letter-spacing: 0.5px;&quot;&gt;有的时候，A 发送数据包的速度太快，而 B 的接收能力不够，但 B 却没有告知 A 这个情况。&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957834484656.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;怎么解决呢？&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;很简单，B 告诉 A 自己的&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;接收能力，A 根据 B 的接收能力，相应控制自己的&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;发送速率&lt;/strong&gt;，就好了。&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;B 怎么告诉 A 呢？B 跟 A 说&amp;quot;我很强&amp;quot;这三个字么？那肯定不行，得有一个严谨的规范。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;于是 B 决定，每次发送数据包给 A 时，顺带传过来一个值，叫&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;窗口大小&lt;/strong&gt;（win)，这个值就表示 B 的&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;接收能力&lt;/strong&gt;。同理，每次 A 给 B 发包时也带上自己的窗口大小，表示 A 的接收能力。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957834326843.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;B 告诉了 A 自己的窗口大小值，A 怎么利用它去做 A 这边发包的流量控制呢？&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;很简单，假如 B 给 A 传过来的窗口大小 win = 5，那 A 根据这个值，把自己要发送的数据分成这么几类。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img width=&quot;800&quot; src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957834210394.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;图片过于清晰，就不再文字解释了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;当 A 不断发送数据包时，&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;已发送的最后一个序号&lt;/strong&gt;就往右移动，直到碰到了窗口的上边界，此时 A 就无法继续发包，达到了流量控制。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957835237214.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;但是当 A 不断发包的同时，A 也会收到来自 B 的确认包，此时&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;整个窗口&lt;/strong&gt;会往右移动，因此上边界也往右移动，A 就能发更多的数据包了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957835516870.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;以上都是在窗口大小不变的情况下，而 B 在发给 A 的 ACK 包中，每一个都可以&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;重新设置&lt;/strong&gt;一个新的窗口大小，如果 A 收到了一个新的窗口大小值，A 会随之调整。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;如果 A 收到了比原窗口值更大的窗口大小，比如 win = 6，则 A 会直接将窗口上边界向右移动 1 个单位。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;img width=&quot;800&quot; src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957835427859.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;如果 A 收到了比原窗口值小的窗口大小，比如 win = 4，则 A 暂时不会改变窗口大小，更不会将窗口上边界向左移动，而是等着 ACK 的到来，不断将左边界向右移动，直到窗口大小值收缩到新大小为止。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957836164552.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: 0px;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;OK，终于将流量控制问题解决得差不多了，你看着上面一个个小动图，给这个窗口起了一个更生动的名字，&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;滑动窗口&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; color: #FF0000;&quot;&gt;拥塞问题&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;但有的时候，不是 B 的接受能力不够，而是网络不太好，造成了&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;网络拥塞&lt;/strong&gt;。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957836840215.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;拥塞控制与流量控制有些像，但流量控制是受 B 的接收能力影响，而拥塞控制是受&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;网络环境&lt;/strong&gt;的影响。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;拥塞控制的解决办法依然是通过设置一定的窗口大小，只不过，流量控制的窗口大小是 B 直接告诉 A 的，而拥塞控制的窗口大小按理说就应该是网络环境主动告诉 A。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;但网络环境怎么可能主动告诉 A 呢？只能 A 单方面通过&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;试探&lt;/strong&gt;，不断感知网络环境的好坏，进而确定自己的拥塞窗口的大小。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957836453993.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;拥塞窗口大小的计算有很多复杂的算法，就不在本文中展开了，假如&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;拥塞窗口的大小为 &amp;nbsp;cwnd&lt;/strong&gt;，上一部分流量控制的&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;滑动窗口的大小为 rwnd&lt;/strong&gt;，那么窗口的右边界受这两个值共同的影响，需要取它俩的最小值。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;窗口大小 = min(cwnd, rwnd)&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;含义很容易理解，当 B 的接受能力比较差时，即使网络非常通畅，A 也需要根据 B 的接收能力限制自己的发送窗口。当网络环境比较差时，即使 B 有很强的接收能力，A 也要根据网络的拥塞情况来限制自己的发送窗口。正所谓受其&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;短板&lt;/strong&gt;的影响嘛~&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; color: #FF0000;&quot;&gt;连接问题&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;有的时候，B 主机的相应进程还没有准备好或是挂掉了，A 就开始发送数据包，导致了浪费。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957837463428.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;这个问题在于，A 在跟 B 通信之前，没有事先确认 B 是否已经准备好，就开始发了一连串的信息。就好比你和另一个人打电话，你还没有&amp;quot;喂&amp;quot;一下确认对方有没有在听，你就巴拉巴拉说了一堆。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;这个问题该怎么解决呢？&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;地球人都知道，&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;三次握手&lt;/strong&gt;嘛！&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;A：我准备好了(SYN)&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;B：我知道了(ACK)，我也准备好了(SYN)&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;A：我知道了(ACK)&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957837359541.gif&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;A 与 B 各自在内存中维护着自己的状态变量，三次握手之后，双方的状态都变成了&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;连接已建立&lt;/strong&gt;（ESTABLISHED）。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;虽然就只是发了三次数据包，并且在各自的内存中维护了状态变量，但这么说总觉得太 low，你看这个过程相当于双方建立连接的过程，于是你灵机一动，就叫它&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;面向连接&lt;/strong&gt;吧。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; color: #888888;&quot;&gt;注意：这个连接是虚拟的，是由 A 和 B 这两个终端共同维护的，在网络中的设备根本就不知道连接这回事儿！&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;但凡事有始就有终，有了建立连接的过程，就要考虑释放连接的过程，又是地球人都知道，&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;四次挥手&lt;/strong&gt;嘛！&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;A：再见，我要关闭了(FIN)&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;B：我知道了(ACK)&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; color: #888888; font-size: 15px;&quot;&gt;&amp;nbsp; &amp;nbsp; &amp;nbsp;给 B 一段时间把自己的事情处理完...&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;B：再见，我要关闭了(FIN)&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin-right: 8px; margin-bottom: 5px; margin-left: 8px; text-indent: 2em; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.75em; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px; font-size: 15px;&quot;&gt;A：我知道了(ACK)&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957837352962.gif&quot; data-catchresult=&quot;img_catchSuccess&quot; width=&quot;&quot; height=&quot;&quot; border=&quot;0&quot; vspace=&quot;0&quot; alt=&quot;&quot; style=&quot;font-family: &amp;quot;Microsoft YaHei&amp;quot;, Helvetica, &amp;quot;STHeiti STXihei&amp;quot;, &amp;quot;Microsoft JhengHei&amp;quot;, Tohoma, Arial; font-size: 14px; padding: 0px; margin: 10px 0px; border: none; width: 530px; height: auto !important;&quot;/&gt;&lt;span style=&quot;font-family: &amp;quot;Microsoft YaHei&amp;quot;, Helvetica, &amp;quot;STHeiti STXihei&amp;quot;, &amp;quot;Microsoft JhengHei&amp;quot;, Tohoma, Arial; font-size: 14px; letter-spacing: 0.015em; text-indent: 2em;&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;strong style=&quot;letter-spacing: 0.015em; padding: 0px; margin: 0px;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #FF0000;&quot;&gt;总结&lt;/span&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;以&lt;/span&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;上讲述&lt;/span&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;的，就是 TCP 协议的核心思想，上面过程中需要传输的信息，就体现在 TCP 协议的头部，这里放上最常见的 TCP 协议头解读的图。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957837806149.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&amp;nbsp;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;不知道你现在再看下面这句话，是否能理解：&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #021EAA;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;TCP 是&lt;/span&gt;&lt;/strong&gt;&lt;/span&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #021EAA;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;面向连接的、可靠的、基于字节流的&lt;/span&gt;&lt;/strong&gt;&lt;/span&gt;&lt;span data-darkreader-inline-color=&quot;&quot; style=&quot;padding: 0px; margin: 0px; color: #021EAA;&quot;&gt;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;传输层通信协议&lt;/span&gt;&lt;/strong&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;面向连接、可靠，这两个词通过上面的讲述很容易理解，那什么叫做基于字节流呢？&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;很简单，TCP 在建立连接时，需要告诉对方 MSS（最大报文段大小）。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;也就是说，如果要发送的数据很大，在 TCP 层是需要按照 MSS 来切割成一个个的&amp;nbsp;&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;TCP 报文段&amp;nbsp;&lt;/strong&gt;的。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;切割的时候我才不管你原来的数据表示什么意思，需要在哪里断句啥的，我就把它当成一串毫无意义的字节，在我想要切割的地方咔嚓就来一刀，标上序号，只要接收方再根据这个序号拼成最终想要的完整数据就行了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;在我 TCP 传输这里，我就把它当做一个个的&lt;strong style=&quot;padding: 0px; margin: 0px;&quot;&gt;字节&lt;/strong&gt;，也就是基于字节流的含义了。&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;padding: 0px; margin: 0px; letter-spacing: 0.5px;&quot;&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755957837168377.png&quot; style=&quot;padding: 0px; margin: 10px 0px; border: none;  height: auto !important;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;&lt;/span&gt;&lt;/p&gt;&lt;p style=&quot;padding: 0px; margin: 13px auto; font-feature-settings: &amp;quot;tnum&amp;quot;; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Segoe UI Emoji&amp;quot;, &amp;quot;Segoe UI Symbol&amp;quot;, &amp;quot;Segoe UI&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Helvetica Neue&amp;quot;, Helvetica, Arial, sans-serif, &amp;quot;Apple Color Emoji&amp;quot;; font-size: 16px; font-variant-numeric: tabular-nums; font-variant-east-asian: normal; font-variant-alternates: normal; font-variant-position: normal; font-variant-emoji: normal; letter-spacing: 0.015em; line-height: 1.8; word-break: break-word; color: rgb(35, 38, 59); text-wrap-mode: wrap; background-color: rgba(255, 255, 255, 0.9); text-align: left;&quot;&gt;&lt;span style=&quot;font-weight: 600; background-color: #FFFFFF; color: #535861; font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Helvetica Neue&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Source Han Sans SC&amp;quot;, &amp;quot;Noto Sans CJK SC&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, &amp;quot;MiSans L3&amp;quot;, sans-serif; font-size: medium;&quot;&gt;后记&lt;/span&gt;&lt;/p&gt;&lt;p data-pid=&quot;LsetG_kH&quot; style=&quot;margin-top: 1.4em; margin-bottom: 1.4em; color: rgb(25, 27, 31); font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Helvetica Neue&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Source Han Sans SC&amp;quot;, &amp;quot;Noto Sans CJK SC&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, &amp;quot;MiSans L3&amp;quot;, sans-serif; font-size: medium; text-wrap-mode: wrap; background-color: rgb(255, 255, 255); text-align: left;&quot;&gt;一提到 TCP，可能很多人都想起被三次握手和四次挥手所支配的恐惧。但其实你跟着文中的思路你就会发现，三次握手与四次挥手只占 TCP 所解决的核心问题中很小的一部分，只是因为它在面试中很适合作为知识点进行考察，所以在很多人的印象中就好像 TCP 的核心就是握手和挥手似的。&lt;/p&gt;&lt;p data-pid=&quot;0SYuqcWV&quot; style=&quot;margin-top: 1.4em; margin-bottom: 1.4em; color: rgb(25, 27, 31); font-family: -apple-system, BlinkMacSystemFont, &amp;quot;Helvetica Neue&amp;quot;, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;Source Han Sans SC&amp;quot;, &amp;quot;Noto Sans CJK SC&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, &amp;quot;MiSans L3&amp;quot;, sans-serif; font-size: medium; text-wrap-mode: wrap; background-color: rgb(255, 255, 255); text-align: left;&quot;&gt;本文希望你能从问题出发，真正理解 TCP 所想要解决的问题，你会发现很多原理就好像生活常识一样顺其自然，并不复杂，希望你有收获～&lt;/p&gt;</description><pubDate>Sat, 23 Aug 2025 22:03:47 +0800</pubDate></item><item><title>图解 | 你管这破玩意儿叫网络？</title><link>http://www.yyk8.cn/?id=51</link><description>&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;你是一台电脑，你的名字叫 A&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    很久很久之前，你不与任何&lt;span class=&quot;words-blog hl-git-1&quot; data-tit=&quot;其他&quot; data-pretit=&quot;其他&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 3px 0px 0px; padding: 0px 18px 0px 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: pointer; background: url(&amp;quot;../img/gitcode-key.png&amp;quot;) right center / 14px 14px no-repeat transparent; box-shadow: none; color: #4EA1DB !important;&quot;&gt;其他&lt;/span&gt;电脑相连接，孤苦伶仃。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919400888177.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    直到有一天，你希望与另一台电脑 B 建立通信，于是你们各开了一个网口，用一根&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;网线&lt;/span&gt;连接了起来。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919401669558.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    用一根网线连接起来怎么就能&amp;quot;通信&amp;quot;了呢？我可以给你讲 IO、讲中断、讲缓冲区，但这不是研究网络时该关心的问题。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如果你纠结，要么去研究一下操作系统是如何处理网络 IO 的，要么去研究一下包是如何被网卡转换成电信号发送出去的，要么就仅仅把它当做电脑里有个小人在&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;开枪&lt;/span&gt;吧~
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919401820534.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    反正，你们就是连起来了，并且可以通信。
&lt;/p&gt;
&lt;h4 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 16px; color: rgb(79, 79, 79); line-height: 26px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t1&quot;&gt;&lt;/a&gt;&lt;a id=&quot;_28&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;第一层
&lt;/h4&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    有一天，一个新伙伴 C 加入了，但聪明的你们很快发现，可以每个人开&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;两个网口&lt;/span&gt;，用一共&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;三根网线&lt;/span&gt;，彼此相连。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919401589729.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    随着越来越多的人加入，你发现身上开的网口实在太多了，而且网线密密麻麻，混乱不堪。（而实际上一台电脑根本开不了这么多网口，所以这种连线只在理论上可行，所以连不上的我就用红色虚线表示了，就是这么严谨哈哈~）
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919401192558.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    于是你们发明了一个中间设备，你们将网线都插到这个设备上，由这个设备做转发，就可以彼此之间通信了，本质上和原来一样，只不过网口的数量和网线的数量减少了，不再那么混乱。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919401725314.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    你给它取名叫&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;集线器&lt;/span&gt;，它仅仅是无脑将电信号&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;转发到所有出口（广播）&lt;/span&gt;，不做任何处理，你觉得它是没有智商的，因此把人家定性在了&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;物理层&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919402513266.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    由于转发到了所有出口，那 BCDE 四台机器怎么知道数据包是不是发给自己的呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    首先，你要给所有的连接到集线器的设备，都起个名字。原来你们叫 ABCD，但现在需要一个更专业的，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;全局唯一&lt;/span&gt;的名字作为标识，你把这个更高端的名字称为&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;MAC 地址&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    你的 MAC 地址是 aa-aa-aa-aa-aa-aa，你的伙伴 b 的 MAC 地址是 bb-bb-bb-bb-bb-bb，以此类推，不重复就好。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这样，A 在发送数据包给 B 时，只要在头部拼接一个这样结构的数据，就可以了。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919402311821.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    B 在收到数据包后，根据头部的目标 MAC 地址信息，判断这个数据包的确是发给自己的，于是便&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;收下&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    其他的 CDE 收到数据包后，根据头部的目标 MAC 地址信息，判断这个数据包并不是发给自己的，于是便&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;丢弃&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919402203054.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    虽然集线器使整个布局干净不少，但原来我只要发给电脑 B 的消息，现在却要发给连接到集线器中的所有电脑，这样既不安全，又不节省网络资源。
&lt;/p&gt;
&lt;h4 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 16px; color: rgb(79, 79, 79); line-height: 26px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t2&quot;&gt;&lt;/a&gt;&lt;a id=&quot;_78&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;第二层
&lt;/h4&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如果把这个集线器弄得更智能一些，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;只发给目标 MAC 地址指向的那台电脑&lt;/span&gt;，就好了。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919403418157.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    虽然只比集线器多了这一点点区别，但看起来似乎有智能了，你把这东西叫做&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;交换机&lt;/span&gt;。也正因为这一点点智能，你把它放在了另一个层级，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;数据链路层&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919403131675.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如上图所示，你是这样设计的。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    交换机内部维护一张&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;MAC 地址表&lt;/span&gt;，记录着每一个 MAC 地址的设备，连接在其哪一个端口上。
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    MAC 地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    端口
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    bb-bb-bb-bb-bb-bb
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    cc-cc-cc-cc-cc-cc
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    3
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    aa-aa-aa-aa-aa-aa
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    4
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    dd-dd-dd-dd-dd-dd
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    5
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    假如你仍然要发给 B 一个数据包，构造了如下的数据结构从网口出去。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919402311821.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    到达交换机时，交换机内部通过自己维护的 MAC 地址表，发现&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;目标机器 B 的 MAC 地址 bb-bb-bb-bb-bb-bb 映射到了端口 1 上&lt;/span&gt;，于是把数据从 1 号端口发给了 B，完事~
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    你给这个通过这样传输方式而组成的小范围的网络，叫做&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;以太网&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    当然最开始的时候，MAC 地址表是空的，是怎么逐步建立起来的呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    假如在 MAC 地址表为空是，你给 B 发送了如下数据
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919402311821.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    由于这个包从端口 4 进入的交换机，所以此时交换机就可以在 MAC地址表记录第一条数据：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;MAC：aa-aa-aa-aa-aa-aa-aa&lt;br style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;/&gt;端口：4&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    交换机看目标 MAC 地址（bb-bb-bb-bb-bb-bb）在地址表中并没有映射关系，于是将此包发给了&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;所有端口&lt;/span&gt;，也即发给了所有机器。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    之后，只有机器 B 收到了确实是发给自己的包，于是做出了&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;响应&lt;/span&gt;，响应数据从端口 1 进入交换机，于是交换机此时在地址表中更新了第二条数据：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;MAC：bb-bb-bb-bb-bb-bb&lt;br style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;/&gt;端口：1&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    过程如下
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919403203120.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    经过该网络中的机器不断地通信，交换机最终将 MAC 地址表建立完毕~
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919403270323.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    随着机器数量越多，交换机的端口也不够了，但聪明的你发现，只要将多个交换机连接起来，这个问题就轻而易举搞定~
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919404672538.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    你完全不需要设计额外的东西，只需要按照之前的设计和规矩来，按照上述的接线方式即可完成所有电脑的互联，所以交换机设计的这种规则，真的很巧妙。你想想看为什么（比如 A 要发数据给 F）。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    但是你要注意，上面那根红色的线，最终在 MAC 地址表中可不是一条记录呀，而是要把 EFGH 这四台机器与该端口（端口6）的映射全部记录在表中。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    最终，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;两个交换机将分别记录 A ~ H 所有机器的映射记录&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;左边的交换机&lt;/span&gt;
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    MAC 地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    端口
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    bb-bb-bb-bb-bb-bb
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    cc-cc-cc-cc-cc-cc
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    3
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    aa-aa-aa-aa-aa-aa
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    4
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    dd-dd-dd-dd-dd-dd
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    5
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    ee-ee-ee-ee-ee-ee
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    6
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    ff-ff-ff-ff-ff-ff
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    6
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    gg-gg-gg-gg-gg-gg
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    6
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    hh-hh-hh-hh-hh-hh
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    6
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;右边的交换机&lt;/span&gt;
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    MAC 地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    端口
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    bb-bb-bb-bb-bb-bb
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    cc-cc-cc-cc-cc-cc
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    aa-aa-aa-aa-aa-aa
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    dd-dd-dd-dd-dd-dd
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    ee-ee-ee-ee-ee-ee
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    2
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    ff-ff-ff-ff-ff-ff
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    3
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    gg-gg-gg-gg-gg-gg
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    4
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    hh-hh-hh-hh-hh-hh
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    6
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这在只有 8 台电脑的时候还好，甚至在只有几百台电脑的时候，都还好，所以这种交换机的设计方式，已经足足支撑一阵子了。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    但很遗憾，人是贪婪的动物，很快，电脑的数量就发展到几千、几万、几十万。
&lt;/p&gt;
&lt;h4 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 16px; color: rgb(79, 79, 79); line-height: 26px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t3&quot;&gt;&lt;/a&gt;&lt;a id=&quot;_187&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;第三层
&lt;/h4&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    交换机已经无法记录如此庞大的映射关系了。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    此时你动了歪脑筋，你发现了问题的根本在于，连出去的那根红色的网线，后面不知道有多少个设备不断地连接进来，从而使得地址表越来越大。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那我可不可以让那根红色的网线，接入一个&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;新的设备&lt;/span&gt;，这个设备就跟电脑一样有自己独立的 MAC 地址，而且同时还能帮我把数据包做一次&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;转发&lt;/span&gt;呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这个设备就是&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;路由器，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;它的功能就是，作为一台独立的拥有 MAC 地址的设备，并且可以帮我把数据包做一次转发&lt;/span&gt;，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;你把它定在了&lt;/span&gt;网络层。&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919404352423.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    注意，路由器的每一个端口，都有独立的 MAC 地址
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    好了，现在交换机的 MAC 地址表中，只需要多出一条 MAC 地址 ABAB 与其端口的映射关系，就可以成功把数据包转交给路由器了，这条搞定。**&lt;br style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;/&gt;**
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那如何做到，把发送给 C 和 D，甚至是把发送给 DEFGH… 的数据包，统统先发送给路由器呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    不难想到这样一个点子，假如电脑 C 和 D 的 MAC 地址拥有共同的前缀，比如分别是
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    **C 的 MAC 地址：FFFF-FFFF-CCCC
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    **
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;D 的 MAC 地址：FFFF-FFFF-DDDD&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那我们就可以说，将目标 MAC 地址为&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;FFFF-FFFF-？开头的&lt;/span&gt;，统统先发送给路由器。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这样是否可行呢？答案是否定的。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    我们先从现实中 MAC 地址的结构入手，MAC地址也叫物理地址、硬件地址，长度为 48 位，一般这样来表示
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;00-16-EA-AE-3C-40&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    它是由网络设备制造商生产时烧录在网卡的EPROM（一种闪存芯片，通常可以通过程序擦写）。其中**前 24 位（00-16-EA）代表网络硬件制造商的编号****，后 24 位（AE-3C-40）是该厂家自己分配的，一般表示系列号。**只要不更改自己的 MAC 地址，MAC 地址在世界是唯一的。形象地说，MAC地址就如同身份证上的身份证号码，具有唯一性。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那如果你希望向上面那样表示将目标 MAC 地址为&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;FFFF-FFFF-？开头的&lt;/span&gt;，统一从路由器出去发给某一群设备（后面会提到这其实是子网的概念），那你就需要要求某一子网下统统买一个厂商制造的设备，要么你就需要要求厂商在生产网络设备烧录 MAC 地址时，提前按照你规划好的子网结构来定 MAC 地址，并且日后这个网络的结构都不能轻易改变。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这显然是不现实的。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    于是你发明了一个新的地址，给每一台机器一个 32 位的编号，如：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;11000000101010000000000000000001&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    你觉得有些不清晰，于是把它分成四个部分，中间用点相连。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;11000000.10101000.00000000.00000001&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    你还觉得不清晰，于是把它转换成 10 进制。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;192.168.0.1&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    最后你给了这个地址一个响亮的名字，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;IP 地址&lt;/span&gt;。现在每一台电脑，同时有自己的 MAC 地址，又有自己的 IP 地址，只不过 IP 地址是&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;软件层面&lt;/span&gt;上的，可以随时修改，MAC 地址一般是无法修改的。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这样一个可以随时修改的 IP 地址，就可以根据你规划的网络拓扑结构，来调整了。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919404189614.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如上图所示，假如我想要发送数据包给 ABCD 其中一台设备，不论哪一台，我都可以这样描述，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;“将 IP 地址为 192.168.0 开头的全部发送给到路由器，之后再怎么转发，交给它！”&lt;/span&gt;，巧妙吧。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那交给路由器之后，路由器又是怎么把数据包准确转发给指定设备的呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    别急我们慢慢来。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    我们先给上面的组网方式中的每一台设备，加上自己的 IP 地址
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919404705969.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    现在两个设备之间传输，除了加上数据链路层的头部之外，还要再增加一个网络层的头部。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    假如 A 给 B 发送数据，由于它们直接连着交换机，所以 A 直接发出如下数据包即可，其实网络层没有体现出作用。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919404841278.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    但假如 A 给 C 发送数据，A 就需要先转交给路由器，然后再由路由器转交给 C。由于最底层的传输仍然需要依赖以太网，所以数据包是分成两段的。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    A ~ 路由器这段的包如下：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919405217293.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    路由器到 C 这段的包如下：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919405598520.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    好了，上面说的两种情况（A-&amp;gt;B，A-&amp;gt;C），相信细心的读者应该会有不少疑问，下面我们一个个来展开。
&lt;/p&gt;
&lt;h3 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 18px; color: rgb(79, 79, 79); line-height: 28px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t4&quot;&gt;&lt;/a&gt;&lt;a id=&quot;A__C__282&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;A 给 C 发数据包，怎么知道是否要通过路由器转发呢？
&lt;/h3&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;答案：子网&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如果源 IP 与目的 IP 处于一个子网，直接将包通过交换机发出去。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如果源 IP 与目的 IP 不处于一个子网，就交给路由器去处理。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    好，那现在只需要解决，什么叫处于一个子网就好了。
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            192.168.0.1 和 192.168.0.2 处于同一个子网
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            192.168.0.1 和 192.168.1.1 处于不同子网
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这两个是我们人为规定的，即我们想表示，对于 192.168.0.1 来说：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;192.168.0.xxx 开头的，就算是在一个子网，否则就是在不同的子网。&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那对于计算机来说，怎么表达这个意思呢？于是人们发明了&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;子网掩码&lt;/span&gt;的概念
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    假如某台机器的子网掩码定为 255.255.255.0
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这表示，将源 IP 与目的 IP 分别同这个子网掩码进行&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;与运算****，相等则是在一个子网，不相等就是在不同子网&lt;/span&gt;，就这么简单。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    比如
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;A电脑&lt;/span&gt;：192.168.0.1 &amp;amp; 255.255.255.0 = 192.168.0.0
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;B电脑&lt;/span&gt;：192.168.0.2 &amp;amp; 255.255.255.0 = 192.168.0.0
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;C电脑&lt;/span&gt;：192.168.1.1 &amp;amp; 255.255.255.0 = 192.168.1.0
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;D电脑&lt;/span&gt;：192.168.1.2 &amp;amp; 255.255.255.0 = 192.168.1.0
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那么 A 与 B 在同一个子网，C 与 D 在同一个子网，但是 A 与 C 就不在同一个子网，与 D 也不在同一个子网，以此类推。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919405332858.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    所以如果 A 给 C 发消息，A 和 C 的 IP 地址分别 &amp;amp; A 机器配置的子网掩码，发现不相等，则 A 认为 C 和自己不在同一个子网，于是把包发给路由器，就不管了，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;之后怎么转发，A 不关心&lt;/span&gt;。
&lt;/p&gt;
&lt;h3 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 18px; color: rgb(79, 79, 79); line-height: 28px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t5&quot;&gt;&lt;/a&gt;&lt;a id=&quot;A__320&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;A 如何知道，哪个设备是路由器？
&lt;/h3&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;答案：在 A 上要设置默认网关&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    上一步 A 通过是否与 C 在同一个子网内，判断出自己应该把包发给路由器，那路由器的 IP 是多少呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    其实说发给路由器不准确，应该说 A 会把包发给&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;默认网关&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    对 A 来说，A 只能&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;直接&lt;/span&gt;把包发给同处于一个子网下的某个 IP 上，所以发给路由器还是发给某个电脑，对 A 来说也不关心，只要这个设备有个 IP 地址就行。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    所以&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;默认网关，就是 A 在自己电脑里配置的一个 IP 地址&lt;/span&gt;，以便在发给不同子网的机器时，发给这个 IP 地址。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919405197306.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    仅此而已！
&lt;/p&gt;
&lt;h3 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 18px; color: rgb(79, 79, 79); line-height: 28px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t6&quot;&gt;&lt;/a&gt;&lt;a id=&quot;C_338&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;路由器如何知道C在哪里？
&lt;/h3&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;答案：路由表&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    现在 A 要给 C 发数据包，已经可以成功发到路由器这里了，最后一个问题就是，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;路由器怎么知道，收到的这个数据包，该从自己的哪个端口出去&lt;/span&gt;，才能直接（或间接）地最终到达目的地 C 呢。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    路由器收到的数据包有目的 IP 也就是 C 的 IP 地址，需要转化成从自己的哪个端口出去，很容易想到，应该有个表，就像 MAC 地址表一样。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这个表就叫&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;路由表&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    至于这个路由表是怎么出来的，有很多路由算法，本文不展开，因为我也不会哈哈~
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    不同于 MAC 地址表的是，路由表并不是一对一这种明确关系，我们下面看一个路由表的结构。
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    目的地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    子网掩码
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    下一跳
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    端口
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.0
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    255.255.255.0
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    0
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.254
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    255.255.255.255
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    0
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.1.0
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    255.255.255.0
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.1.254
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    255.255.255.255
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    我们学习一种新的表示方法，由于子网掩码其实就表示前多少位表示子网的网段，所以如 192.168.0.0（255.255.255.0） 也可以简写为 192.168.0.0/24
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    目的地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    下一跳
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    端口
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.0/24
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    0
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.254/32
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    0
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.1.0/24
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.1.254/32
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这就很好理解了，路由表就表示，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;192.168.0.xxx 这个子网下的，都转发到 0 号端口，192.168.1.xxx 这个子网下的，都转发到 1 号端口&lt;/span&gt;。下一跳列还没有值，我们先不管
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    配合着结构图来看（这里把子网掩码和默认网关都补齐了）图中 &amp;amp; 笔误，结果应该是 .0
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;https://i-blog.csdnimg.cn/blog_migrate/498ce4cfb2289412e7018664d87c2a6e.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; class=&quot;loadingclass&quot;/&gt;
&lt;/p&gt;
&lt;h3 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 18px; color: rgb(79, 79, 79); line-height: 28px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t7&quot;&gt;&lt;/a&gt;&lt;a id=&quot;_IP__MAC__IP__378&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;刚才说的都是 IP 层，但发送数据包的数据链路层需要知道 MAC 地址，可是我只知道 IP 地址该怎么办呢？
&lt;/h3&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;答案：arp&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    假如你（A）此时&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;不知道&lt;/span&gt;你同伴 B 的 MAC 地址（现实中就是不知道的，刚刚我们只是假设已知），你只知道它的 IP 地址，你该怎么把数据包准确传给 B 呢？
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    答案很简单，在网络层，&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;我需要把 IP 地址对应的 MAC 地址找到&lt;/span&gt;，也就是通过某种方式，找到&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;192.168.0.2&lt;/span&gt;&amp;nbsp;对应的 MAC 地址&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;BBBB&lt;/span&gt;。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这种方式就是&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;arp 协议&lt;/span&gt;，同时电脑 A 和 B 里面也会有一张&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;arp 缓存表&lt;/span&gt;，表中记录着&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;IP 与 MAC 地址&lt;/span&gt;的对应关系。
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    IP 地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    MAC 地址
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.2
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    BBBB
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    一开始的时候这个表是&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;空的&lt;/span&gt;，电脑 A 为了知道电脑 B（192.168.0.2）的 MAC 地址，将会&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;广播&lt;/span&gt;一条 arp 请求，B 收到请求后，带上自己的 MAC 地址给 A 一个&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;响应&lt;/span&gt;。此时 A 便更新了自己的 arp 表。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这样通过大家不断广播 arp 请求，最终所有电脑里面都将 arp 缓存表更新完整。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;总结一下&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    好了，总结一下，到目前为止就几条规则
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;从各个节点的视角来看&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;电脑视角&lt;/span&gt;**：**
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            首先我要知道我的 IP 以及对方的 IP
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            通过子网掩码判断我们是否在同一个子网
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            在同一个子网就通过 arp 获取对方 mac 地址直接扔出去
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            不在同一个子网就通过 arp 获取默认网关的 mac 地址直接扔出去
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;交换机视角：&lt;/span&gt;
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            我收到的数据包必须有目标 MAC 地址
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            通过 MAC 地址表查映射关系
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            查到了就按照映射关系从我的指定端口发出去
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            查不到就所有端口都发出去
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;路由器视角：&lt;/span&gt;
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            我收到的数据包必须有目标 IP 地址
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            通过路由表查映射关系
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            查到了就按照映射关系从我的指定端口发出去（不在任何一个子网范围，走其路由器的默认网关也是查到了）
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            查不到则返回一个路由不可达的数据包
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    如果你嗅觉足够敏锐，你应该可以感受到下面这句话：
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    网络层（IP协议）本身没有传输包的功能，包的实际传输是委托给数据链路层（以太网中的交换机）来实现的。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;涉及到的三张表分别是&lt;/span&gt;
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            交换机中有&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;MAC 地址&lt;/span&gt;表用于映射 MAC 地址和它的端口
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            路由器中有&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;路由表&lt;/span&gt;用于映射 IP 地址(段)和它的端口
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            电脑和路由器中都有&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;arp 缓存表&lt;/span&gt;用于缓存 IP 和 MAC 地址的映射关系
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;这三张表是怎么来的&lt;/span&gt;
&lt;/p&gt;
&lt;ul style=&quot;box-sizing: border-box; outline: 0px; margin-bottom: 24px; padding: 0px; list-style-position: initial; list-style-image: initial; font-size: 16px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot; class=&quot; list-paddingleft-2&quot;&gt;
    &lt;li&gt;
        &lt;p&gt;
            MAC 地址表是通过以太网内各节点之间不断通过交换机通信，不断完善起来的。
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            路由表是各种路由算法 + 人工配置逐步完善起来的。
        &lt;/p&gt;
    &lt;/li&gt;
    &lt;li&gt;
        &lt;p&gt;
            arp 缓存表是不断通过 arp 协议的请求逐步完善起来的。
        &lt;/p&gt;
    &lt;/li&gt;
&lt;/ul&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    知道了以上这些，目前网络上两个节点是如何发送数据包的这个过程，就完全可以解释通了！
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    那接下来我们就放上本章&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;最后一个&lt;/span&gt;&amp;nbsp;网络拓扑图吧，请做好&amp;nbsp;&lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;战斗&lt;/span&gt;&amp;nbsp;准备！
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919406972602.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    这时路由器 1 连接了路由器 2，所以其路由表有了下一条地址这一个概念，所以它的路由表就变成了这个样子。如果匹配到了有下一跳地址的一项，则需要再次匹配，找到其端口，并找到下一跳 IP 的 MAC 地址。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    也就是说找来找去，最终必须能映射到一个端口号，然后从这个端口号把数据包发出去。
&lt;/p&gt;
&lt;div class=&quot;table-box&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 0px 24px; padding: 0px; font-synthesis-style: auto; overflow-wrap: break-word; overflow-x: auto; color: rgba(0, 0, 0, 0.75); font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-size: 16px; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;table width=&quot;962&quot;&gt;
        &lt;thead style=&quot;box-sizing: border-box; outline: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot; class=&quot;firstRow&quot;&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    目的地址
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    下一跳
                &lt;/th&gt;
                &lt;th align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; background-color: rgb(239, 243, 245); word-break: normal !important;&quot;&gt;
                    端口
                &lt;/th&gt;
            &lt;/tr&gt;
        &lt;/thead&gt;
        &lt;tbody style=&quot;box-sizing: border-box; outline: 0px; border: 0px; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.0/24
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    0
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.0.254/32
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    0
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.1.0/24
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.1.254/32
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    1
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.2.0/24
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.100.5
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); background-color: rgb(247, 247, 247); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.100.0/24
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    2
                &lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr style=&quot;box-sizing: border-box; outline: 0px; border-width: 1px 0px 0px; border-right-style: initial; border-bottom-style: initial; border-left-style: initial; border-right-color: initial; border-bottom-color: initial; border-left-color: initial; border-image: initial; border-top-style: solid; border-top-color: rgb(221, 221, 221); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    192.168.100.4/32
                &lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;&lt;/td&gt;
                &lt;td align=&quot;center&quot; style=&quot;box-sizing: border-box; outline: 0px; padding: 8px; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; font-size: 14px; color: rgb(79, 79, 79); line-height: 22px; vertical-align: middle; word-break: normal !important;&quot;&gt;
                    2
                &lt;/td&gt;
            &lt;/tr&gt;
        &lt;/tbody&gt;
    &lt;/table&gt;
&lt;/div&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;这时如果 A 给 F 发送一个数据包，能不能通呢？如果通的话整个过程是怎样的呢？&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919406778204.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    思考一分钟…
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;详细过程动画描述：&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;https://i-blog.csdnimg.cn/blog_migrate/f86fc3e69c5ec0239f2e4ac70131400a.gif&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; class=&quot;loadingclass&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;详细过程文字描述：&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;1.&lt;/span&gt;&amp;nbsp;首先 A（192.168.0.1）通过子网掩码（255.255.255.0）计算出自己与 F（192.168.2.2）并不在同一个子网内，于是决定发送给默认网关（192.168.0.254）
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;2.&lt;/span&gt;&amp;nbsp;A 通过 ARP 找到 默认网关 192.168.0.254 的 MAC 地址。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;3.&lt;/span&gt;&amp;nbsp;A 将源 MAC 地址（AAAA）与网关 MAC 地址（ABAB）封装在数据链路层头部，又将源 IP 地址（192.168.0.1）和目的 IP 地址（192.168.2.2）（注意这里千万不要以为填写的是默认网关的 IP 地址，从始至终这个数据包的两个 IP 地址都是不变的，只有 MAC 地址在不断变化）封装在网络层头部，然后发包
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919406279830.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;4.&lt;/span&gt;&amp;nbsp;交换机 1 收到数据包后，发现目标 MAC 地址是 ABAB，转发给路由器1
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;5.&lt;/span&gt;&amp;nbsp;数据包来到了路由器 1，发现其目标 IP 地址是 192.168.2.2，查看其路由表，发现了下一跳的地址是 192.168.100.5
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;6.&lt;/span&gt;&amp;nbsp;所以此时路由器 1 需要做两件事，第一件是再次匹配路由表，发现匹配到了端口为 2，于是将其封装到数据链路层，最后把包从 2 号口发出去。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;7.&lt;/span&gt;&amp;nbsp;此时路由器 2 收到了数据包，看到其目的地址是 192.168.2.2，查询其路由表，匹配到端口号为 1，准备从 1 号口把数据包送出去。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;8.&lt;/span&gt;&amp;nbsp;但此时路由器 2 需要知道 192.168.2.2 的 MAC 地址了，于是查看其 arp 缓存，找到其 MAC 地址为 FFFF，将其封装在数据链路层头部，并从 1 号端口把包发出去。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;9.&lt;/span&gt;&amp;nbsp;交换机 3 收到了数据包，发现目的 MAC 地址为 FFFF，查询其 MAC 地址表，发现应该从其6 号端口出去，于是从 6 号端口把数据包发出去。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;10.&lt;/span&gt;&amp;nbsp;**F 最终收到了数据包！**并且发现目的 MAC 地址就是自己，于是收下了这个包
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;span style=&quot;box-sizing: border-box; outline: 0px; font-weight: 700; font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;更详细且精准的过程：&lt;/span&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    读到这相信大家已经很累了，理解上述过程基本上网络层以下的部分主流程就基本疏通了，如果你想要本过程更为专业的过程描述，可以在公众号&amp;quot;低并发编程&amp;quot;后台回复&amp;quot;网络&amp;quot;，获得我模拟这个过程的 Cisco&amp;nbsp;&lt;span class=&quot;words-blog hl-git-1&quot; data-tit=&quot;Packet&quot; data-pretit=&quot;packet&quot; style=&quot;box-sizing: border-box; outline: 0px; margin: 0px 3px 0px 0px; padding: 0px 18px 0px 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: pointer; background: url(&amp;quot;../img/gitcode-key.png&amp;quot;) right center / 14px 14px no-repeat transparent; box-shadow: none; color: #4EA1DB !important;&quot;&gt;Packet&lt;/span&gt;&amp;nbsp;Tracer 源文件。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919406817133.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    每一步包的传输都会有各层的原始数据，以及专业的过程描述
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919408527486.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    同时在此基础之上你也可以设计自己的网络拓扑结构，进行各种实验，来加深网络传输过程的理解。
&lt;/p&gt;
&lt;h4 style=&quot;box-sizing: border-box; outline: 0px; margin: 24px 0px 8px; padding: 0px; font-family: &amp;quot;PingFang SC&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, SimHei, Arial, SimSun; font-size: 16px; color: rgb(79, 79, 79); line-height: 26px; font-synthesis-style: auto; overflow-wrap: break-word; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;a style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot; name=&quot;t8&quot;&gt;&lt;/a&gt;&lt;a id=&quot;_527&quot; style=&quot;box-sizing: border-box; outline: none; margin: 0px; padding: 0px; font-weight: normal; cursor: pointer; background-color: transparent; color: rgb(78, 161, 219); font-synthesis-style: auto; overflow-wrap: break-word;&quot;&gt;&lt;/a&gt;后记
&lt;/h4&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    至此，经过物理层、数据链路层、网络层这前三层的协议，以及根据这些协议设计的各种网络设备（网线、集线器、交换机、路由器），理论上只要拥有对方的 IP 地址，就已经将地球上任意位置的两个节点连通了。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    &lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2025/08/202508231755919408615454.png&quot; alt=&quot;图片&quot; style=&quot;box-sizing: border-box; outline: none; border: 0px none; margin: 0px; font-synthesis-style: auto; overflow-wrap: break-word; cursor: zoom-in;&quot; data-catchresult=&quot;img_catchSuccess&quot;/&gt;
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    本文经过了很多次的修改，删减了不少影响主流程的内容，就是为了让读者能抓住网络传输前三层的真正核心思想。同时网络相关的知识也是多且杂，我也还有很多搞不清楚的地方，非常欢迎大家与我交流，共同进步。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    读到这里都是真爱了，当然要赠一个投票。
&lt;/p&gt;
&lt;p style=&quot;box-sizing: border-box; outline: 0px; margin-top: 0px; margin-bottom: 16px; padding: 0px; font-size: 16px; color: rgb(77, 77, 77); line-height: 26px; overflow: auto hidden; font-synthesis-style: auto; overflow-wrap: break-word; font-family: -apple-system, &amp;quot;SF UI Text&amp;quot;, Arial, &amp;quot;PingFang SC&amp;quot;, &amp;quot;Hiragino Sans GB&amp;quot;, &amp;quot;Microsoft YaHei&amp;quot;, &amp;quot;WenQuanYi Micro Hei&amp;quot;, sans-serif; font-variant-ligatures: no-common-ligatures; text-wrap-mode: wrap; background-color: rgb(255, 255, 255);&quot;&gt;
    完
&lt;/p&gt;
&lt;p&gt;
    &lt;br/&gt;
&lt;/p&gt;</description><pubDate>Sat, 23 Aug 2025 11:06:39 +0800</pubDate></item><item><title>tr069服务器建设</title><link>http://www.yyk8.cn/?id=49</link><description>&lt;head&gt;&lt;/head&gt;&lt;body&gt;&lt;p&gt;TR069（Technical Report 069，由Broadband Forum制定）是用于远程管理网络终端设备（如光猫、路由器、机顶盒等CPE设备）的协议，其核心是通过&lt;strong&gt;ACS（Auto-Configuration Server，自动配置服务器）&lt;/strong&gt; 与CPE之间的交互，实现设备注册、配置下发、状态监控、固件升级等功能。建设TR069服务器（即ACS服务器）需要结合协议规范、技术选型、架构设计和运维需求，以下是详细说明：&lt;/p&gt;
&lt;h3 id=&quot;h3-u4E00u3001TR069u670Du52A1u5668uFF08ACSuFF09u7684u6838u5FC3u529Fu80FD-4&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;一、TR069服务器（ACS）的核心功能&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;一、TR069服务器（ACS）的核心功能&lt;/h3&gt;&lt;p&gt;在建设前需明确ACS的核心目标，其功能覆盖设备全生命周期管理：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;设备注册与身份认证&lt;/strong&gt;：CPE启动后通过TR069协议发现ACS，并完成身份验证（如序列号、MAC地址、证书校验）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;参数配置&lt;/strong&gt;：通过&lt;code&gt;SetParameterValues&lt;/code&gt;等RPC方法，向CPE下发配置（如网络参数、端口映射、QoS策略）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;状态监控&lt;/strong&gt;：通过&lt;code&gt;GetParameterValues&lt;/code&gt;获取CPE状态（如在线状态、信号强度、流量统计）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;固件/软件升级&lt;/strong&gt;：通过&lt;code&gt;Download&lt;/code&gt;方法推送固件镜像，支持批量升级、断点续传和失败回滚。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;故障诊断&lt;/strong&gt;：接收CPE主动上报的故障事件（如断网、参数异常），触发告警或自动修复。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;事件通知处理&lt;/strong&gt;：处理CPE的Bootstrapping（启动）、ValueChange（参数变化）等事件。&lt;/li&gt;&lt;/ul&gt;
&lt;h3 id=&quot;h3-u4E8Cu3001TR069u670Du52A1u5668u5EFAu8BBEu6B65u9AA4-14&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;二、TR069服务器建设步骤&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;二、TR069服务器建设步骤&lt;/h3&gt;&lt;h4 id=&quot;h4-1.20u9700u6C42u5206u6790-15&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;1. 需求分析&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;1. 需求分析&lt;/h4&gt;&lt;p&gt;需明确核心需求，避免过度设计或功能缺失：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;设备规模&lt;/strong&gt;：管理的CPE数量（如10万级、百万级），决定服务器性能和架构复杂度。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;设备类型&lt;/strong&gt;：支持的CPE型号（如光猫、企业路由器），需兼容不同厂商的协议实现（可能存在厂商自定义参数）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;功能优先级&lt;/strong&gt;：是否需要批量升级、自定义配置模板、API对接（如与OSS/BSS系统集成）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;安全性要求&lt;/strong&gt;：是否需加密传输（HTTPS）、双向认证（证书）、防恶意接入。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;可用性要求&lt;/strong&gt;：是否需高可用（集群部署）、灾备能力（多区域部署）。&lt;/li&gt;&lt;/ul&gt;
&lt;h4 id=&quot;h4-2.20u6280u672Fu9009u578BuFF1Au5F00u6E9020vs20u81EAu7814-24&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;2. 技术选型：开源 vs 自研&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;2. 技术选型：开源 vs 自研&lt;/h4&gt;&lt;p&gt;根据需求选择合适的技术路线：&lt;/p&gt;
&lt;table&gt;
&lt;thead&gt;
&lt;tr&gt;
&lt;th&gt;方案&lt;/th&gt;
&lt;th&gt;优势&lt;/th&gt;
&lt;th&gt;劣势&lt;/th&gt;
&lt;th&gt;适用场景&lt;/th&gt;
&lt;/tr&gt;
&lt;/thead&gt;
&lt;tbody&gt;
&lt;tr&gt;
&lt;td&gt;开源方案&lt;/td&gt;
&lt;td&gt;成本低、成熟度高（经社区验证）&lt;/td&gt;
&lt;td&gt;定制化能力有限，大规模部署需二次开发&lt;/td&gt;
&lt;td&gt;中小规模设备管理、快速上线需求&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;自主研发&lt;/td&gt;
&lt;td&gt;可深度定制，适配特殊需求&lt;/td&gt;
&lt;td&gt;开发周期长、需专业协议人才&lt;/td&gt;
&lt;td&gt;大规模设备管理、复杂业务场景（如运营商级）&lt;/td&gt;
&lt;/tr&gt;
&lt;/tbody&gt;
&lt;/table&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;主流开源方案&lt;/strong&gt;：GenieACS（最流行，支持TR069核心功能，含CWMP协议处理、北向API、文件服务器组件）、OpenACS（轻量型，适合简单场景）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;自研核心依赖&lt;/strong&gt;：需基于TR069协议规范（如BBF TR-069 Amendment 10）开发，涉及SOAP协议（TR069基于SOAP）、HTTP通信、XML解析、设备参数树（如TR-098/TR-106定义的参数路径）。&lt;/li&gt;&lt;/ul&gt;
&lt;h4 id=&quot;h4-3.20u67B6u6784u8BBEu8BA1-36&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;3. 架构设计&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;3. 架构设计&lt;/h4&gt;&lt;p&gt;需满足&lt;strong&gt;可扩展性、高可用性、安全性&lt;/strong&gt;，典型架构如下：&lt;/p&gt;
&lt;pre&gt;&lt;code&gt;[CPE设备] → [负载均衡器（Nginx/HAProxy）] → [ACS集群（协议处理节点）] → [数据库/缓存]
                                 ↓
                        [监控/日志系统（Prometheus/ELK）]
&lt;/code&gt;&lt;/pre&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;前端层&lt;/strong&gt;：负载均衡器分发CPE的连接请求，实现流量分担和故障转移；同时终止HTTPS连接（配置SSL证书），确保传输加密。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;ACS核心层&lt;/strong&gt;：&lt;ul&gt;
&lt;li&gt;协议处理节点：运行TR069协议逻辑（如会话管理、RPC方法处理），可水平扩展以应对高并发。&lt;/li&gt;&lt;li&gt;北向接口（NBI）：提供RESTful API，供管理平台（如Web控制台、OSS系统）调用，实现配置下发、状态查询。&lt;/li&gt;&lt;li&gt;文件服务器：存储固件镜像、配置模板，支持CPE通过&lt;code&gt;Download&lt;/code&gt;方法获取资源。&lt;/li&gt;&lt;/ul&gt;
&lt;/li&gt;&lt;li&gt;&lt;strong&gt;数据层&lt;/strong&gt;：&lt;ul&gt;
&lt;li&gt;数据库：存储设备信息（序列号、型号）、配置参数、历史数据（如升级记录），可选MySQL/PostgreSQL（结构化数据）或MongoDB（非结构化参数树）。&lt;/li&gt;&lt;li&gt;缓存：用Redis缓存高频访问数据（如设备在线状态），减少数据库压力。&lt;/li&gt;&lt;/ul&gt;
&lt;/li&gt;&lt;li&gt;&lt;strong&gt;监控与日志&lt;/strong&gt;：&lt;ul&gt;
&lt;li&gt;监控：用Prometheus采集服务器CPU、内存、并发连接数，以及CPE在线率、会话成功率等指标，通过Grafana可视化。&lt;/li&gt;&lt;li&gt;日志：用ELK栈（Elasticsearch+Logstash+Kibana）收集协议交互日志、错误日志，用于问题排查。&lt;/li&gt;&lt;/ul&gt;
&lt;/li&gt;&lt;/ul&gt;
&lt;h4 id=&quot;h4-4.20u6838u5FC3u6280u672Fu5B9Eu73B0u7EC6u8282-58&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;4. 核心技术实现细节&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;4. 核心技术实现细节&lt;/h4&gt;&lt;p&gt;无论开源还是自研，需重点关注TR069协议的核心交互逻辑：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;p&gt;&lt;strong&gt;会话建立流程&lt;/strong&gt;：&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;CPE通过DHCP选项（如Option 43）或静态配置获取ACS地址（如&lt;code&gt;https://acs.example.com:7547&lt;/code&gt;）。&lt;/li&gt;&lt;li&gt;CPE发起HTTP POST请求（SOAP信封），触发会话建立，ACS验证CPE身份（如用户名密码、证书）。&lt;/li&gt;&lt;li&gt;会话过程中，ACS与CPE通过RPC方法交互（如&lt;code&gt;GetParameterValues&lt;/code&gt;查询设备序列号，&lt;code&gt;SetParameterValues&lt;/code&gt;下发DNS配置）。&lt;/li&gt;&lt;/ol&gt;
&lt;/li&gt;&lt;li&gt;&lt;p&gt;&lt;strong&gt;关键RPC方法&lt;/strong&gt;：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;code&gt;GetParameterValues&lt;/code&gt;：ACS获取CPE的参数值（如&lt;code&gt;InternetGatewayDevice.WANDevice.1.WANConnectionDevice.1.Status&lt;/code&gt;）。&lt;/li&gt;&lt;li&gt;&lt;code&gt;SetParameterValues&lt;/code&gt;：ACS向CPE设置参数（如&lt;code&gt;InternetGatewayDevice.LAN.IPAddress&lt;/code&gt;设为&lt;code&gt;192.168.1.1&lt;/code&gt;）。&lt;/li&gt;&lt;li&gt;&lt;code&gt;Download&lt;/code&gt;：ACS通知CPE下载资源（如固件URL），支持进度反馈和校验（MD5）。&lt;/li&gt;&lt;li&gt;&lt;code&gt;Inform&lt;/code&gt;：CPE主动向ACS上报事件（如启动完成、参数变化）。&lt;/li&gt;&lt;/ul&gt;
&lt;/li&gt;&lt;li&gt;&lt;p&gt;&lt;strong&gt;设备参数树&lt;/strong&gt;：TR069基于TR-098、TR-106定义了标准化参数路径（如&lt;code&gt;DeviceInfo.SerialNumber&lt;/code&gt;为设备序列号），需确保服务器支持主流厂商的参数扩展（如华为光猫的自定义OID）。&lt;/p&gt;
&lt;/li&gt;&lt;/ul&gt;
&lt;h4 id=&quot;h4-5.20u5B89u5168u6027u8BBEu8BA1-75&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;5. 安全性设计&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;5. 安全性设计&lt;/h4&gt;&lt;p&gt;TR069涉及设备远程控制，安全性至关重要：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;传输加密&lt;/strong&gt;：强制使用HTTPS（TLS 1.2+），配置可信CA证书，防止数据被窃听或篡改。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;身份认证&lt;/strong&gt;：&lt;ul&gt;
&lt;li&gt;设备认证：验证CPE的序列号、MAC地址或预共享密钥（PSK），拒绝未授权设备接入。&lt;/li&gt;&lt;li&gt;双向认证：通过客户端证书（CPE）和服务器证书（ACS）实现双向TLS，适用于高安全场景（如企业网）。&lt;/li&gt;&lt;/ul&gt;
&lt;/li&gt;&lt;li&gt;&lt;strong&gt;权限控制&lt;/strong&gt;：北向接口需支持RBAC（基于角色的访问控制），限制管理员操作范围（如只读用户无法执行升级）。&lt;/li&gt;&lt;/ul&gt;
&lt;h4 id=&quot;h4-6.20u6D4Bu8BD5u4E0Eu9A8Cu8BC1-84&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;6. 测试与验证&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;6. 测试与验证&lt;/h4&gt;&lt;p&gt;上线前需通过多维度测试确保稳定性：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;功能测试&lt;/strong&gt;：验证核心功能（如配置下发后CPE是否生效、升级是否成功），覆盖所有RPC方法。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;兼容性测试&lt;/strong&gt;：测试主流厂商CPE（华为、中兴、烽火等），解决协议实现差异（如部分厂商对&lt;code&gt;Download&lt;/code&gt;超时处理不同）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;性能测试&lt;/strong&gt;：用压测工具（如JMeter模拟CPE连接），验证服务器在10万级并发下的响应时间（目标：单次会话处理&amp;lt;1秒）。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;灾备测试&lt;/strong&gt;：模拟节点故障，验证集群自动切换能力；测试数据库备份恢复流程。&lt;/li&gt;&lt;/ul&gt;
&lt;h4 id=&quot;h4-7.20u8FD0u7EF4u4E0Eu4F18u5316-92&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;7. 运维与优化&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;7. 运维与优化&lt;/h4&gt;&lt;p&gt;上线后需建立完善的运维体系：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;设备管理&lt;/strong&gt;：支持批量导入设备、按区域/型号分组，简化配置模板复用。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;告警机制&lt;/strong&gt;：设置阈值（如CPE离线超30分钟、升级失败率&amp;gt;5%），通过短信/邮件推送告警。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;性能优化&lt;/strong&gt;：&lt;ul&gt;
&lt;li&gt;数据库：分库分表（按设备ID哈希）处理千万级设备数据，优化查询索引。&lt;/li&gt;&lt;li&gt;缓存：延长在线设备状态的缓存时间，减少数据库访问。&lt;/li&gt;&lt;li&gt;批量任务：错峰执行固件升级（如夜间），避免服务器负载过高。&lt;/li&gt;&lt;/ul&gt;
&lt;/li&gt;&lt;li&gt;&lt;strong&gt;日志分析&lt;/strong&gt;：通过日志定位通信失败原因（如“会话超时”可能是CPE网络不稳定或服务器过载）。&lt;/li&gt;&lt;/ul&gt;
&lt;h3 id=&quot;h3-u4E09u3001u5EF6u4F38uFF1ATR069u7684u53D1u5C55u4E0Eu6269u5C55-103&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;三、延伸：TR069的发展与扩展&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;三、延伸：TR069的发展与扩展&lt;/h3&gt;&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;协议扩展&lt;/strong&gt;：最新的TR069 Amendment 10支持WebSockets（替代HTTP长轮询），提升实时性；TR-157扩展了IPv6设备管理能力。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;云化部署&lt;/strong&gt;：将ACS部署在公有云（如AWS、阿里云），利用云弹性扩展应对设备数量增长，降低硬件投入。&lt;/li&gt;&lt;li&gt;&lt;strong&gt;与其他协议融合&lt;/strong&gt;：可与SNMP（局域网管理）、MQTT（物联网设备）结合，构建全域设备管理平台。&lt;/li&gt;&lt;/ul&gt;
&lt;h3 id=&quot;h3-u603Bu7ED3-109&quot;&gt;&lt;a class=&quot;reference-link&quot; name=&quot;总结&quot;&gt;&lt;/a&gt;&lt;span class=&quot;header-link octicon octicon-link&quot;&gt;&lt;/span&gt;总结&lt;/h3&gt;&lt;p&gt;TR069服务器建设的核心是&lt;strong&gt;“合规性+可扩展性+安全性”&lt;/strong&gt;：需严格遵循协议规范确保设备兼容，通过集群架构和云化设计支撑大规模设备，同时强化加密与认证保障远程管理安全。对于中小规模场景，推荐基于GenieACS二次开发；运营商级场景则需自研高可用架构，结合监控与运维体系实现高效管理。&lt;/p&gt;
&lt;/body&gt;</description><pubDate>Sun, 03 Aug 2025 10:49:10 +0800</pubDate></item><item><title>使用android逆向助手，进行反编译apk，查看apk源码</title><link>http://www.yyk8.cn/?id=47</link><description>&lt;p&gt;第一步：下载逆向助手：(链接: https://pan.baidu.com/s/15jtoFDg9LWV80HREeyx5HA 提取码: k527 )&lt;/p&gt;&lt;p&gt;第二步：将apk文件拷贝到逆向助手的apktool目录，并CD到当前目录下：&lt;/p&gt;&lt;p&gt;第三步：在cmd命令行中输入命令 apktool d -f 应用程序名,如：&amp;nbsp;apktool d -f com.google.earth_190791304.apk&amp;nbsp;，回车&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2021/04/20210409173940_57367.png&quot; alt=&quot;&quot; style=&quot;margin: 0px; padding: 0px; border: 0px; height: auto; max-width: 700px;&quot;/&gt;&lt;/p&gt;&lt;p&gt;可以看到生成了以apk名字命名的文件夹，里面可以直接看到res目录下的资源文件和android的清单文件，但是看不到java文件&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2021/04/20210409173940_58701.png&quot; alt=&quot;&quot; style=&quot;margin: 0px; padding: 0px; border: 0px; height: auto; max-width: 700px;&quot;/&gt;&lt;/p&gt;&lt;p&gt;第四步：双击打开Android逆向助手.exe，选中“提取dex”操作，然后将lib\apktool目录下的apk拖动到源文件中；点击“操作”，得到dex文件&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2021/04/20210409173940_27096.png&quot; alt=&quot;&quot; style=&quot;margin: 0px; padding: 0px; border: 0px; height: auto; max-width: 700px;&quot;/&gt;&lt;/p&gt;&lt;p&gt;第五步：选中“dex转jar”操作，然后将得到的dex文件拖动到源文件中；点击“操作”，得到jar文件，jd工具会自动打开jar文件，这样就看到java源码了（如果应用进行了混淆，看到的源码类和方法都是abc等）&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2021/04/20210409173941_65213.png&quot; alt=&quot;&quot; style=&quot;margin: 0px; padding: 0px; border: 0px; height: auto; max-width: 700px;&quot;/&gt;&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2021/04/20210409173941_21572.png&quot; alt=&quot;&quot; style=&quot;margin: 0px; padding: 0px; border: 0px; height: auto; max-width: 700px;&quot;/&gt;&lt;/p&gt;&lt;p&gt;&lt;img src=&quot;http://www.yyk8.cn/zb_users/upload/2021/04/20210409173941_39437.png&quot; alt=&quot;&quot; style=&quot;margin: 0px; padding: 0px; border: 0px; height: auto; max-width: 700px;&quot;/&gt;&lt;/p&gt;&lt;p&gt;有时候反编译Apk时，日志显示反编译已经完成，但是打开反编译出来的文件夹发现文件夹为空，这是因为Android逆向助手很久没更新，Android逆向助手lib中的Apktoo版本过老不支持这个Apk的Android平台，这个时候我们可以通过手动更新lib下的Apktool来解决&lt;br style=&quot;margin: 0px; padding: 0px;&quot;/&gt;这里我提供一个GitHub链接，Apktool更新地址：&lt;a href=&quot;https://ibotpeaches.github.io/Apktool/&quot; rel=&quot;nofollow&quot; target=&quot;_blank&quot;&gt;https://ibotpeaches.github.io/Apktool/&lt;/a&gt;&lt;/p&gt;&lt;p&gt;拿到最新版的Apktool之后，我们把apktool.jar放到Android逆向助手的\lib\Apktool下，这时候我们就可以进行反编译了。&lt;/p&gt;&lt;p&gt;&lt;br/&gt;&lt;/p&gt;</description><pubDate>Tue, 15 Sep 2020 17:31:51 +0800</pubDate></item><item><title>华为MA5680T OLT GPON/EPON配置指导</title><link>http://www.yyk8.cn/?id=45</link><description>&lt;p&gt;MA5680T配置指导（适用于V800R006C02版本）&lt;br/&gt;《1-常用命令》&lt;br/&gt;//登陆用户名root，密码 admin&lt;br/&gt;MA5680T&amp;gt;enable&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //打开特权EXEC&lt;br/&gt;MA5680T#config&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //进入终端配置模式&lt;br/&gt;MA5680T(config)#sysname&amp;nbsp; SJZ-HW-OLT-1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //设备命名 (一般为开局配置)&lt;br/&gt;MA5680T(config)#switch language-mode&amp;nbsp; //切换语言,可以在中英文语言中转换。&lt;br/&gt;MA5680T (config) #terminal user name&amp;nbsp;&amp;nbsp; //添加操作用户huawei&lt;br/&gt;&amp;nbsp; User Name(length&amp;lt;6,15&amp;gt;):huawei&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //设置用户名&lt;br/&gt;&amp;nbsp; User Password(length&amp;lt;6,15&amp;gt;):huawei123&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //要求输入密码.输入部分实际为不可见的&lt;br/&gt;&amp;nbsp; Confirm Password(length&amp;lt;6,15&amp;gt;): huawei123&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //要求再次确认一遍密码&lt;br/&gt;&amp;nbsp; User profile name(&amp;lt;=15 chars)[root]:root&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //输入用户管理级别&lt;br/&gt;&amp;nbsp; User&amp;#39;s Level:&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1. Common User&amp;nbsp; 2. Operator&amp;nbsp; 3. Administrator:3&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //选择用户权限&lt;br/&gt;&amp;nbsp; Permitted Reenter Number(0--4):1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //设置此用户名可重复登录次数，一般要求为1次&lt;br/&gt;&amp;nbsp; User&amp;#39;s Appended Info(&amp;lt;=30 chars):HuaweiAdm&amp;nbsp;&amp;nbsp; //添加描述，可不设置。&lt;br/&gt;&amp;nbsp; Adding user succeeds&lt;br/&gt;Repeat this operation? (y/n)[n]:&lt;br/&gt;MA5680T(config)#display board 0&amp;nbsp; //检查设备单板状态，此命令最常用。&lt;br/&gt;&amp;nbsp; -------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; SlotID&amp;nbsp;&amp;nbsp; BoardName&amp;nbsp;&amp;nbsp; Status&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; SubType0 SubType1&amp;nbsp;&amp;nbsp;&amp;nbsp; Online/Offline&lt;br/&gt;&amp;nbsp; -------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H802EPBC&amp;nbsp;&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H802EPBC&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 3&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H802EPBC&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 4&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H802EPBC&amp;nbsp;&amp;nbsp; Auto_find&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 5&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 6&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 7&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801SCUL&amp;nbsp;&amp;nbsp; Active_normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 8&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801SCUL&amp;nbsp;&amp;nbsp; Standby_normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 9&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 10&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 11&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 12&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 13&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 14&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 15&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 16&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 17&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801GICF&amp;nbsp;&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 18&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801X2CA&amp;nbsp;&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 19&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 19&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 20&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; -------------------------------------------------------------------------&lt;br/&gt;MA5680T(config)#board confirm 0&amp;nbsp;&amp;nbsp;&amp;nbsp; //对于自动发现的单板，需要确认后，单板才能使用。&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //对于未确认的单板，单板硬件运行指示灯正常，但是业务端口无法工作。&lt;br/&gt;《2-开局配置命令》&lt;br/&gt;MA5680T (config)#vlan 99 smart&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //增加设备管理VLAN (一般为开局配置)&lt;br/&gt;MA5680T (config)#vlan 10 smart&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //增加语音业务VLAN (一般为开局配置)&lt;br/&gt;MA5680T (config)#port vlan 99&amp;nbsp; 0/18&amp;nbsp; 0&amp;nbsp; //将管理VLAN透传到上行端口. (一般为开局配置)&lt;br/&gt;MA5680T (config)#port vlan 10&amp;nbsp; 0/17&amp;nbsp; 1&amp;nbsp;&amp;nbsp; //将语音业务VLAN透传到上行端口(一般为开局配置)&lt;br/&gt;// 0/18 0&amp;nbsp; 意思为第0框(默认框号) / 第18槽位(槽位编号，一般在机框上都有标出)&amp;nbsp; 0端口(上行口编号)&lt;br/&gt;MA5680T (config)#vlan desc 99 description NMS VLAN&amp;nbsp; //添加vlan的描述, (一般为开局配置)&lt;br/&gt;MA5680T (config)#vlan desc 10 description NGN-VPN&amp;nbsp; &lt;br/&gt;//配置设备管理地址，(一般为开局配置)&lt;br/&gt;MA5680T (config)#interface vlanif 99&amp;nbsp; &lt;br/&gt;MA5680T (config-if-vlanif99)#ip address 172.16.21.2 255.255.255.0&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;MA5680T (config-if-vlanif99)#quit&amp;nbsp;&amp;nbsp; &lt;br/&gt;MA5680T (config)#ip route-static 0.0.0.0 0.0.0.0 172.16.21.1&amp;nbsp;&amp;nbsp;&amp;nbsp; //配置设备缺省路由 (一般为开局配置)&lt;br/&gt;MA5680T (config)#ip route-static 10.0.0.0 255.0.0.0 10.50.42.1&amp;nbsp;&amp;nbsp;&amp;nbsp; //配置语音部分路由 (一般为开局配置)&lt;br/&gt;//设置上行端口速率以及双工模式 (一般为开局配置)&lt;br/&gt;MA5680T (config)#interface giu 0/17&lt;br/&gt;MA5680T (config-if-giu-0/17)#speed 0 1000&amp;nbsp;&amp;nbsp; //配置端口速率，GE口只能配置成1000, 10GE口只能配置成10000&lt;br/&gt;MA5680T (config-if-giu-0/17)#speed 1 1000&lt;br/&gt;MA5680T (config-if-giu-0/17)#duplex 0 full&amp;nbsp;&amp;nbsp; //配置双工模式，half为半双工，full为全双工&lt;br/&gt;MA5680T (config-if-giu-0/17)#duplex 1 full&lt;br/&gt;MA5680T (config-if-giu-0/17)#auto-neg 0 disable&amp;nbsp;&amp;nbsp;&amp;nbsp; //配置自协商模式，disable为禁止自协商，enable为允许&lt;br/&gt;MA5680T (config-if-giu-0/17)#auto-neg 1 disable&lt;br/&gt;MA5680T (config-if-giu-0/17)#quit&lt;br/&gt;//在终端配置模式下添加网管SNMP参数&lt;br/&gt;snmp-agent community read public&amp;nbsp;&amp;nbsp;&amp;nbsp; //设置读参数&lt;br/&gt;snmp-agent community write private&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //设置写参数&lt;br/&gt;snmp-agent sys-info contact HUAWEI TEL:4008302118&amp;nbsp; //设置SNMP联系信息&lt;br/&gt;snmp-agent sys-info location SHIJIAZHUANG UNIONCOM NETWORKSTATIONM&amp;nbsp; //设置SNMP本地信息&lt;br/&gt;snmp-agent sys-info version v1&amp;nbsp; //设置SNMP版本信息&lt;br/&gt;snmp-agent target-host trap-hostname N2000SERVER address 172.16.255.2 udp-port 161 trap-paramsname private&lt;br/&gt;//设置网管参数，N2000SERVER为网管计算机名称，172.16.255.2为网管地址。通信端口一般为161，读串为private&lt;br/&gt;//以下为添加的两个综合网管的管理参数。&lt;br/&gt;snmp-agent target-host trap-hostname public.61.182.202.57 address 61.182.202.57 trap-paramsname public&lt;br/&gt;snmp-agent target-host trap-hostname public.61.182.202.46 address 61.182.202.46 trap-paramsname public&lt;br/&gt;snmp-agent target-host trap-paramsname private v1 securityname private&lt;br/&gt;snmp-agent target-host trap-paramsname public v1 securityname public&lt;br/&gt;snmp-agent trap enable standard&amp;nbsp; //启用SNMP 标准 trap报文功能&lt;br/&gt;//查看EMU电源监控信息.如果没有需要新建系统环境监控模块&lt;br/&gt;MA5680T (config)# display emu 0&lt;br/&gt;MA5680T (config)# emu del 0&amp;nbsp;&amp;nbsp;&amp;nbsp; //如果EMU电源模块添加不正确，需要删除EMU重新添加。此为删除命令&lt;br/&gt;Are you sure to delete this EMU?(y/n)[n]:y&lt;br/&gt;MA5680T (config)# emu add 0 FAN 0 1 H801FCBC&amp;nbsp;&amp;nbsp; //新建EMU环境监控电源模块.&lt;br/&gt;MA5680T (config)#display emu&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //EMU被正确装入的情况下，查看后显示信息如下：&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; EMU ID: 0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; EMU name&amp;nbsp;&amp;nbsp; : H801FCBC&lt;br/&gt;&amp;nbsp; EMU type&amp;nbsp;&amp;nbsp;&amp;nbsp; : FAN&lt;br/&gt;&amp;nbsp; Used or not&amp;nbsp;&amp;nbsp; : Used&lt;br/&gt;&amp;nbsp; EMU state&amp;nbsp;&amp;nbsp; : Normal&lt;br/&gt;&amp;nbsp; Frame ID&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0&lt;br/&gt;&amp;nbsp; Subnode&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 1&lt;br/&gt;&amp;nbsp; ----------------------------------------------------------------------------&lt;br/&gt;MA5680T (config)#interface emu 0&amp;nbsp;&amp;nbsp; //进入电源模块0.&lt;br/&gt;MA5680T (config-if-fan-0)# fan speed mode automatic&amp;nbsp; //修改电源风扇速度.&lt;br/&gt;MA5680T (config-if-fan-0)#quit&lt;br/&gt;//配置业务单板数据,需要打开ONU自动发现功能.否则下挂设备之后无法在OLT上查看到新发现的设备。.&lt;br/&gt;MA5680T (config)#interface epon 0/1&amp;nbsp; //进入EPON命令模式&lt;br/&gt;MA5680T (config-if-epon-0/1)#port 0 ont-auto-find enable&amp;nbsp;&amp;nbsp; // 打开1槽位各业务端口的ONT自动发现功能&lt;br/&gt;MA5680T (config-if-epon-0/1)#port 1 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-epon-0/1)#port 2 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-epon-0/1)#port 3 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-epon-0/1)#quit&lt;br/&gt;MA5680T (config)#interface gpon 0/2&amp;nbsp;&amp;nbsp; //进入GPON命令模式&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 0 ont-auto-find enable&amp;nbsp;&amp;nbsp; // 打开OLT2槽位单板各端口的ONT自动发现功能&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 1 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 2 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 3 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 4 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 5 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 6 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#port 7 ont-auto-find enable&lt;br/&gt;MA5680T (config-if-gpon-0/2)#quit&lt;br/&gt;……&lt;br/&gt;//设置完成进行保存&lt;br/&gt;MA5680T (config)#save&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //保存配置信息。 切记操作完成之后保存。&lt;br/&gt;《3-业务配置命令》&lt;br/&gt;第一步：创建业务vlan，并在上行口作透传&lt;br/&gt;MA5680T (config)#vlan 2223 smart&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //增加业务VLAN。所有业务vlan均采用SMART VLAN属性&lt;br/&gt;MA5680T (config)#vlan 200 smart&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //增加专线VLAN&lt;br/&gt;MA5680T (config)#port vlan 2223&amp;nbsp; 0/18&amp;nbsp; 0&amp;nbsp;&amp;nbsp; //将业务VLAN透传到上行端口&lt;br/&gt;MA5680T (config)#port vlan 200&amp;nbsp; 0/18&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp; //将专线VLAN透传到上行口&lt;br/&gt;//如果不确定上行口，可以通过以下命令查询上行口配置进行参考。&lt;br/&gt;MA5680T(config)# display current-configuration section vlan&amp;nbsp;&amp;nbsp; //查看配置文件中的VLAN配置，参考端口配置部分&lt;br/&gt;……&lt;br/&gt;Port vlan&amp;nbsp; xxx&amp;nbsp; 0/18 0&lt;br/&gt;……&lt;br/&gt;MA5680T (config)#vlan desc 2223 description&amp;nbsp; 604-MianSiXiaoQu&amp;nbsp;&amp;nbsp; //添加业务描述&lt;br/&gt;第二步：查看DBA模板，如果没有，需要创建&lt;br/&gt;MA5680T (config)#display dba-profile all&amp;nbsp; //查看OLT的 DBA能力集模板.&lt;br/&gt;//1-9 为系统自带的DBA能力集模板。&lt;br/&gt;//DBA是基于整个ONT调度的，需根据ONT的业务类型和用户数选择适合的带宽类型和带宽大小。&lt;br/&gt;//注意fix带宽和assure带宽之和不能大于PON接口总带宽。&lt;br/&gt;关于开局DBA模板的选择&lt;br/&gt;当前设备默认的dba模板是保证10M，最大15M，这对于一般的ONU设备以及通用场景，是没有问题的，但是对于某些特殊场景，需要注意DBA模板的设置。&lt;br/&gt;1、 高密度设备：如UA5000或者MA5600使用EPON上行的，设备用户数超过300以上。&lt;br/&gt;2、 同时在线用户较多的：如MA5616设备，最大接入用户128个，而同时在线用户超过90个。&lt;br/&gt;3、 高带宽需求的：部分地方的用户对上行带宽需求较多（提供下载等）&lt;br/&gt;上述场景对于15M的设备上行总带宽已经明显不足。&lt;br/&gt;针对上述问题，对DBA模板的配置做如下要求：&lt;br/&gt;1） 一般场景下，配置dba模板为type3，保证带宽20M，最大带宽50M&lt;br/&gt;2） 包括但不限于上述场景下，配置dba模板也为type3，保证带宽30M，最大带宽100M&lt;br/&gt;//添加自定义的dba模板.这里分别设置1M,2M,4M,6M,8M,10M,20M,30M,50M,100M的能力集模板,方便日后使用.&lt;br/&gt;dba-profile add profile-id 11 profile-name 1M type3 assure 1024 max 2048&lt;br/&gt;dba-profile add profile-id 12 profile-name 2M type3 assure 2048 max 4096&lt;br/&gt;dba-profile add profile-id 14 profile-name 4M type3 assure 4096 max 8192&lt;br/&gt;dba-profile add profile-id 16 profile-name 6M type3 assure 6144 max 12288&lt;br/&gt;dba-profile add profile-id 18 profile-name 8M type3 assure 8192 max 16384&lt;br/&gt;dba-profile add profile-id 10 profile-name 10M type3 assure 10240 max 20480&lt;br/&gt;dba-profile add profile-id 20 profile-name 20M type3 assure 20480 max 40960&lt;br/&gt;dba-profile add profile-id 30 profile-name 30M type3 assure 30720 max 61440&lt;br/&gt;dba-profile add profile-id 50 profile-name 50M type3 assure 51200 max 102400&lt;br/&gt;dba-profile add profile-id 100 profile-name 100M type3 assure 102400 max 204800&lt;br/&gt;//类型(type)分为5种，分别是type1,type2,type3,type4,type5.其中：&lt;br/&gt;//type1 为固定带宽模式；&lt;br/&gt;//type2 为保证带宽模式；&lt;br/&gt;//type3 为保证带宽的同时设置最大带宽值；&lt;br/&gt;//type4 为仅设定最大带宽模式；&lt;br/&gt;//type5 为3种模式的综合，即设置最大带宽，在保证带宽的同时采用固定带宽模式。&lt;br/&gt;MA5680T (config)#display dba-profile profile-id 20&amp;nbsp;&amp;nbsp; //查看DBA模板20&lt;br/&gt;&amp;nbsp; -----------------------------------------------------------------&lt;br/&gt;&amp;nbsp; Profile-name :&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 20M&lt;br/&gt;&amp;nbsp; Profile-ID:&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 20&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; type :&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 3&lt;br/&gt;&amp;nbsp; Bandwidth compensation:&amp;nbsp;&amp;nbsp; No&lt;br/&gt;&amp;nbsp; Fix(kbps):&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; Assure (kbps):&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 20480 &lt;br/&gt;&amp;nbsp; Max (kbps):&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 40960 &lt;br/&gt;&amp;nbsp; bind-times :&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1&lt;br/&gt;&amp;nbsp; -----------------------------------------------------------------&lt;br/&gt;MA5680T (config)# dba-profile delete profile-id 20&amp;nbsp;&amp;nbsp;&amp;nbsp; //删除DBA模板,前提是此DBA模板没有被任何线路模板绑定。&lt;br/&gt;MA5680T (config)# dba-profile modify profile-id 20&amp;nbsp;&amp;nbsp;&amp;nbsp; //修改DBA模板，前提是此DBA模板没有被任何线路模板绑定。&lt;br/&gt;第三步：查看线路模板，如果没有，需要创建&lt;br/&gt;MA5680T(config)#display ont-lineprofile epon all&amp;nbsp;&amp;nbsp; //查看EPON业务线路模板&lt;br/&gt;MA5680T(config)#display ont-lineprofile gpon all&amp;nbsp;&amp;nbsp; //查看GPON业务线路模板&lt;br/&gt;//系统默认没有线路模板，需创建线路模板1并进入到线路模板模式，系统最多支持4096个线路模板&lt;br/&gt;//每个模板均可被ONU终端重复绑定。&lt;br/&gt;MA5680T(config)#ont-lineprofile epon profile-name MDU profile-id 1&lt;br/&gt;MA5680T(config-epon-lineprofile-1)#quit&lt;br/&gt;//添加线路模板（编号）1.不设置任何参数，系统会默认使用DBA模板9绑定此线路模板。ONU开局绑定此模板。&lt;br/&gt;//添加用户自定义的EPON线路模板,主要针对实现不同业务的终端使用&lt;br/&gt;MA5680T(config)#ont-lineprofile epon profile-id 100 profile-name 100M&amp;nbsp;&amp;nbsp;&amp;nbsp; //创建100M线路模板，绑定DBA模板100&lt;br/&gt;MA5680T(config-epon-lineprofile-100)#llid dba-profile-id 100&lt;br/&gt;//线路模板绑定DBA模板，支持下行加密，系统支持aes-128，triple-churining两种加密方式，默认加密关闭。&lt;br/&gt;MA5680T(config-epon-lineprofile-100)#commit&amp;nbsp;&amp;nbsp; //注意,添加的线路模板需要提交命令才被接受并保存下来.&lt;br/&gt;MA5680T(config-epon-lineprofile-100)#quit&lt;br/&gt;//按照以上方式添加其他线路模板:分别添加1M,2M,4M,6M,8M,10M,20M,30M,50M线路模板&lt;br/&gt;//设置10M模板，保证10M带宽。&lt;br/&gt;MA5680T(config)#ont-lineprofile epon profile-name 10M profile-id 10&amp;nbsp; &lt;br/&gt;MA5680T(config-epon-lineprofile-10)#llid dba-profile-id 10&lt;br/&gt;MA5680T(config-epon-lineprofile-10)#commit&lt;br/&gt;MA5680T(config-epon-lineprofile-10)#quit&lt;br/&gt;……&lt;br/&gt;MA5680T(config)#ont-lineprofile epon profile-name 50M profile-id 50&lt;br/&gt;MA5680T(config-epon-lineprofile-50)#llid dba-profile-id 50&lt;br/&gt;MA5680T(config-epon-lineprofile-50)#commit&lt;br/&gt;MA5680T(config-epon-lineprofile-50)#quit&lt;/p&gt;&lt;p&gt;Interface gpon 0/1&lt;br/&gt;Display ont info 0 5&lt;br/&gt;//添加GPON线路模板，这里针对普通业务的线路模板,采用优先级配置的方式实现.&lt;br/&gt;&amp;gt;严格优先级队列调度&lt;br/&gt;给每个队列赋予不同的优先级，每次调度时，最先对具有最高优先级的非空队列中的报文进行服务。严格优先级队列调度严格按照优先级从高到低的次序优先发送较高优先级队列中的报文，当较高优先级队列为空时，再发送较低优先级队列中的报文。&lt;br/&gt;Priority参数： VLAN优先级&lt;br/&gt;0: Best effort 1: Background 2: Spare 3: Excellent effort 4: Controlled load 5: Video 6: Voice 7: Network control&lt;br/&gt;MA5680T(config)# ont-lineprofile gpon profile-name gpon-onu profile-id 20&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# mapping-mode priority&amp;nbsp;&amp;nbsp; //Gem port端口映射为优先级映射(默认为vlan映射)&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)#tcont 1 dba-profile-id 2&amp;nbsp;&amp;nbsp; // Tcont 1用于管理通道，和dba模板2绑定&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# tcont 2 dba-profile-id 1&amp;nbsp;&amp;nbsp; // Tcont 2用于语音通道，和dba模板1绑定&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# tcont 3 dba-profile-id 50&amp;nbsp; // Tcont 3用于数据业务，和dba模板50绑定&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# gem add 0 eth tcont 1 priority-queue 5&amp;nbsp; //建立Gem port，绑定相应的Tcont通道。&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# gem add 1 eth tcont 2 priority-queue 6&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# gem add 2 eth tcont 3 priority-queue 0&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# gem mapping 0 0 priority 5&amp;nbsp;&amp;nbsp;&amp;nbsp; //建立GEM Port端口映射，这里使用优先级映射。&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# gem mapping 1 0 priority 6&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)# gem mapping 2 0 priority 0&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)#commit&lt;br/&gt;MA5680T(config-gpon-lineprofile-20)#quit&lt;br/&gt;//添加GPON线路模板，这里针对FTTH业务的线路模板&lt;br/&gt;MA5680T(config)# ont-lineprofile gpon profile-name hg8240 profile-id 24&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# mapping-mode vlan&amp;nbsp;&amp;nbsp; //设置映射模式为vlan映射&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# qos-mode gem-car&amp;nbsp;&amp;nbsp;&amp;nbsp; //设置qos模式为gem-car方式&lt;br/&gt;//绑定tcont和dba模板，缺省情况下，tcont 0和dba模板1绑定，不需配置。&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# tcont 1 dba-profile-id 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; // Tcont 1用于管理通道，和dba模板2绑定&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# tcont 2 dba-profile-id 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; // Tcont 2用于语音通道，和dba模板2绑定&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# tcont 3 dba-profile-id 10&amp;nbsp;&amp;nbsp;&amp;nbsp; // Tcont 3用于数据业务，和dba模板10绑定&lt;br/&gt;//TCONT0仅用于OMCI管理使用。如果管理业务和其他业务使用Tcont0，会导致业务不通。&lt;br/&gt;//HG8240可以实现宽窄带业务，配置3条TCONT通道，分别承载不同的业务。1用于管理，2用于语音，3用于数据。&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem add 0 eth tcont 1 gem-car 6&amp;nbsp; //添加GEM PORT，使用流量模板6&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem add 1 eth tcont 2 gem-car 6&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem add 2 eth tcont 3 gem-car 6&lt;br/&gt;//设置映射关系，建立业务通道和GEM PORT的映射。GEMPORT 1 对应语音业务，GEMPORT 2 对应宽带业务。&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem mapping 0 0 vlan 100&amp;nbsp;&amp;nbsp; //设置映射关系，这里的GEMPORT 0 用于管理。&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem mapping 1 0 vlan 10&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem mapping 2 0 vlan 11&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem mapping 2 1 vlan 12&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem mapping 2 2 vlan 13&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# gem mapping 2 3 vlan 14&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)# commit&lt;br/&gt;MA5680T(config-gpon-lineprofile-24)#quit&lt;br/&gt;//查看线路模板和业务模板配置：&lt;br/&gt;MA5680T(config)#display ont-lineprofile epon profile-id 50&lt;br/&gt;MA5680T(config)#display ont-lineprofile gpon profile-id 24&lt;br/&gt;//删除线路模板或业务模板&lt;br/&gt;MA5680T(config)#undo ont-lineprofile epon profile-id 50&amp;nbsp;&amp;nbsp; //删除线路模板50&lt;br/&gt;MA5680T(config)#undo ont-lineprofile gpon profile-name hg8240&amp;nbsp;&amp;nbsp; //删除线路模板hg8240&lt;br/&gt;第四步：查看业务模板，如果没有，需要创建&lt;br/&gt;业务模板是针对ONT的上的业务，涉及到设备接口相关的配置。对于MA561X和MA562X这类SNMP管理模式的终端涉及接口相关配置一般在设备上去完成，因此不需配置业务模板。而对于81X,82X系列等家庭终端设备则需要配置相关的业务模板。&lt;br/&gt;MA5680T(config)#display ont-srvprofile epon all&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //查询ONU业务模板。&lt;br/&gt;Failure: The service profile does not exist&lt;br/&gt;//依据业务需求的不同，需要创建唯一的EPON业务模板与之绑定。&lt;br/&gt;MA5680T(config)#ont-srvprofile epon profile-id 1&amp;nbsp; profile-name SJZ_CheGuanSuo_H810e&lt;br/&gt;MA5680T(config-epon-srvprofile-1)#ont-port eth 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;//H810E为1个网口，设置参数为1。若是H813E为4个网口，此处参数设置为4。&lt;br/&gt;{ &amp;lt;cr&amp;gt;|pots&amp;lt;K&amp;gt;|tdm-type&amp;lt;K&amp;gt;|tdm&amp;lt;K&amp;gt; }:&lt;br/&gt;&amp;nbsp; Command:&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; ont-port eth 1&lt;br/&gt;MA5680T(config-epon-srvprofile-1)#port vlan eth 1 200&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //将专线VLAN绑定到终端端口&lt;br/&gt;MA5680T(config-epon-srvprofile-1)#commit&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //交之后生效&lt;br/&gt;MA5680T(config-epon-srvprofile-1)#quit&lt;br/&gt;//添加GPON业务模板，这里针对HG850A/HG8240为例配置相应的业务模板&lt;br/&gt;MA5680T(config)# ont-srvprofile gpon profile-name hg8240 profile-id 24&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# ont-port pots 2 eth 4&amp;nbsp;&amp;nbsp;&amp;nbsp; //设置中断端口数量。850A/8240固定提供4FE+2POTS&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# multicast-forward untag&lt;br/&gt;//划分端口vlan，HG850/HG8240的管理报文和语音报文通过IPHOST虚拟端口承载&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# port vlan iphost 100&amp;nbsp; &lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# port vlan iphost 10&lt;br/&gt;//划分端口vlan，ONT的eth用于承载宽带业务,如果采用双层vlan，各端口和vlan对应。&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# port vlan eth 1 11&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# port vlan eth 2 12&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# port vlan eth 3 13&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# port vlan eth 4 14&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# commit&lt;br/&gt;MA5680T(config-gpon-srvprofile-24)# quit&lt;br/&gt;MA5680T(config)# undo ont-srvprofile epon profile-id 1&amp;nbsp; //删除业务模板&lt;br/&gt;第五步：检查SNMP模板参数，检查ONU注册情况。&lt;br/&gt;MA5680T(config)#display snmp-profile all&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //查看olt的SNMP能力集模板.没有需要添加。&lt;br/&gt;注 :对于HG系列以及MA5606T，UA5000等通过OAM管理模式配置的，不需要考虑此参数。&lt;br/&gt;对于MA561X和MA562X，因为是通过SNMP管理模式配置的，需要设置此参数，可以远程下达SNMP网管参数。&lt;br/&gt;//添加olt的SNMP能力集模板&lt;br/&gt;MA5680T(config)#snmp-profile add profile-id 1 profile-name n2000 v1 public private 172.16.255.2 161 n2000&lt;br/&gt;//查看自动返现的ONU信息：&lt;br/&gt;MA5680T(config)#display ont autofind all&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //查看OLT自动发现的ONU信息.&lt;br/&gt;&amp;nbsp;&amp;nbsp; ------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp; Number&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 1&lt;br/&gt;&amp;nbsp;&amp;nbsp; F/S/P&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0/2/1&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ont Mac&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 001D-6A3C-6614&lt;br/&gt;&amp;nbsp;&amp;nbsp; Password&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; :&lt;br/&gt;&amp;nbsp;&amp;nbsp; VenderID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : HWTC&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ontmodel&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 810e&lt;br/&gt;&amp;nbsp;&amp;nbsp; OntSoftwareVersion&amp;nbsp; : V100R001C01B020&lt;br/&gt;&amp;nbsp;&amp;nbsp; OntHardwareVersion&amp;nbsp; : HG810e &lt;br/&gt;&amp;nbsp;&amp;nbsp; Ont autofind time&amp;nbsp;&amp;nbsp; : 2010-06-06 15:01:52&lt;br/&gt;&amp;nbsp;&amp;nbsp; ------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp; Number&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 2&lt;br/&gt;&amp;nbsp;&amp;nbsp; F/S/P&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0/1/0&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ont Mac&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0000-0000-0000&lt;br/&gt;&amp;nbsp;&amp;nbsp; Password&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 00000000000000000000000000000000&lt;br/&gt;&amp;nbsp;&amp;nbsp; VenderID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : HWTC&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ontmodel&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 5620&lt;br/&gt;&amp;nbsp;&amp;nbsp; OntSoftwareVersion&amp;nbsp; : V8R307 C00&lt;br/&gt;&amp;nbsp;&amp;nbsp; OntHardwareVersion&amp;nbsp; : MA5620&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ont autofind time&amp;nbsp;&amp;nbsp; : 2010-06-09 00:17:17&lt;br/&gt;&amp;nbsp;&amp;nbsp; ------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp; Number&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 3&lt;br/&gt;&amp;nbsp;&amp;nbsp; F/S/P&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0/4/0&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ont Mac&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0018-82EB-51B3&lt;br/&gt;&amp;nbsp;&amp;nbsp; Password&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 00000000000000000000000000000000&lt;br/&gt;&amp;nbsp;&amp;nbsp; VenderID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : HWTC&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ontmodel&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : MDU&lt;br/&gt;&amp;nbsp;&amp;nbsp; OntSoftwareVersion&amp;nbsp; : V8R306C01B053&lt;br/&gt;&amp;nbsp;&amp;nbsp; OntHardwareVersion&amp;nbsp; : MA5616&lt;br/&gt;&amp;nbsp;&amp;nbsp; Ont autofind time&amp;nbsp;&amp;nbsp; : 2010-6-31 16:40:54&lt;br/&gt;&amp;nbsp;&amp;nbsp; ------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp; The number of EPON autofind ONT is 3&lt;br/&gt;注 : 对于某些新开局的OLT,要特别注意是否开局启用了ONU自动发现功能.否则始终无法查看到上报的ONU信息.见开局配置&lt;br/&gt;第六步：添加业务数据&lt;br/&gt;情景一：EPON组网，下挂ONU终端。&lt;br/&gt;MA5680T(config)#interface epon 0/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //进入到EPON单板模式。&lt;br/&gt;//注册或者确认ONU终端，可以实现离线添加数据，但要清楚设备上联端口和地址码信息。&lt;br/&gt;MA5680T (config-if-epon-0/1)# ont add 0&amp;nbsp; 0&amp;nbsp; mac-auth 0000-0000-0000 snmp ont-lineprofile-id 1 des To_604MianSiXQ&lt;br/&gt;或：&lt;br/&gt;MA5680T (config-if-epon-0/1)# ont confirm 0 ontid 0 mac-auth 0000-0000-0000 snmp ont-lineprofile-id 1&lt;br/&gt;//依据设备类型不同,添加ONU的具体参数不同。&lt;br/&gt;&amp;gt;EPON MA562x/MA561x系列设备：&lt;br/&gt;ont add 0 0 mac-auth 0000-0000-0000 snmp ont-lineprofile-id 1 des To_&lt;br/&gt;&amp;gt;EPON MA5606T系列设备/H81x系列设备&lt;br/&gt;ont add 0 0 mac-auth 0000-0000-0000 oam ont-lineprofile-id 1 des To_&lt;br/&gt;&amp;gt;UA5000系列走epon上行&lt;br/&gt;ont add 0 0 mac-auth 0000-0000-0000 oam ont-lineprofile-id 1 des To_&lt;br/&gt;//添加SNMP参数，(凡通过SNMP管理方式注册的ONU终端，需要远程下发SNMP)&lt;br/&gt;ont snmp-profile 0 1 profile-id 1&lt;br/&gt;//配置ONU的管理信息，(凡通过SNMP管理方式注册的ONU终端，需要配置远程管理)&lt;br/&gt;ont ipconfig 0 1 ip-address 172.16.21.3 mask 255.255.255.0 gateway 172.16.21.1 manage-vlan 99 priority 0&lt;br/&gt;//退出PON板模式&lt;br/&gt;quit&lt;br/&gt;//配置业务流PVC,创建vlan交换&lt;br/&gt;service-port vlan 10 epon 0/1/0 ont 0 multi-service user-vlan 10 inbound traffic-table index 6 outbound traffic-table index 6&lt;br/&gt;service-port vlan 99 epon 0/1/0 ont 0 multi-service user-vlan 99 inbound traffic-table index 6 outbound traffic-table index 6&lt;br/&gt;service-port vlan * epon 0/1/0 ont 0 multi-service user-vlan * inbound traffic-table index 6 outbound traffic-table index 6&lt;br/&gt;//保存数据&lt;br/&gt;save&lt;br/&gt;情景二：普通业务，GPON组网，下挂ONU终端。&lt;br/&gt;MA5680T(config)#interface gpon 0/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //进入到GPON单板模式。&lt;br/&gt;//注册或者确认ONU终端，可以实现离线添加数据，但要清楚设备上联端口和地址码信息。&lt;br/&gt;&amp;gt;GPON MA562x/MA561x系列设备：&lt;br/&gt;ont add 0 0 sn-auth 0000000000000000 snmp ont-lineprofile-id 1 des To_&lt;br/&gt;//添加SNMP参数，(凡通过SNMP管理方式注册的ONU终端，需要远程下发SNMP)&lt;br/&gt;ont snmp-profile 0 0 profile-id 1&lt;br/&gt;//配置ONU的管理信息，(凡通过SNMP管理方式注册的ONU终端，需要配置远程管理)&lt;br/&gt;ont ipconfig 0 0 static ip-address 172.16.21.3 mask 255.255.255.0 gateway 172.16.21.1 vlan 99 priority 0&lt;br/&gt;//退出PON板模式&lt;br/&gt;quit&lt;br/&gt;//配置业务流PVC,创建vlan交换&lt;br/&gt;service-port vlan 10 gpon 0/1/0 ont 0 gemport 1 multi-service user-vlan 10 rx-cttr 6 tx-cttr 6&lt;br/&gt;service-port vlan 99 gpon 0/1/0 ont 0 gemport 1 multi-service user-vlan 99 rx-cttr 6 tx-cttr 6&lt;br/&gt;service-port vlan 222 gpon 0/1/0 ont 0 gemport 2 multi-service user-vlan 222 rx-cttr 6 tx-cttr 6&lt;br/&gt;//保存数据&lt;br/&gt;save&lt;br/&gt;情景三：FTTH业务，GPON组网，下挂ONT终端。&lt;br/&gt;MA5680T(config)#interface gpon 0/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //进入到GPON单板模式。&lt;br/&gt;//注册或者确认ONT终端，可以实现离线添加数据，但要清楚设备上联端口和地址码信息。&lt;br/&gt;ont add 0 0 sn-auth 0000000000000000 omci ont-lineprofile-id 24 ont-srvprofile-id 24 des To_&lt;br/&gt;//添加ONT的native-vlan&lt;br/&gt;ont port native-vlan 0 0 iphost vlan 10&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //iphost是个虚拟端口，是ONT的管理通道和语音通道&lt;br/&gt;ont port native-vlan 0 0 eth 1 vlan 11&lt;br/&gt;ont port native-vlan 0 0 eth 2 vlan 12&lt;br/&gt;ont port native-vlan 0 0 eth 3 vlan 13&lt;br/&gt;ont port native-vlan 0 0 eth 4 vlan 14&lt;br/&gt;quit&lt;br/&gt;//添加业务虚接口，这里数据业务采用了地址转换。&lt;br/&gt;service-port vlan 10 gpon 0/1/0 ont 0 gemport 1 multi-service user-vlan 10 rx-cttr 6 tx-cttr 6&lt;br/&gt;service-port vlan 222 gpon 0/1/0 ont 0 gemport 2 multi-service user-vlan 11 tag-transform translate-and-add inner-vlan 501 inner-priority 0 rx-cttr 6 tx-cttr 6&lt;br/&gt;service-port vlan 222 gpon 0/1/0 ont 0 gemport 2 multi-service user-vlan 12 tag-transform translate-and-add inner-vlan 502 inner-priority 0 rx-cttr 6 tx-cttr 6&lt;br/&gt;service-port vlan 222 gpon 0/1/0 ont 0 gemport 2 multi-service user-vlan 13 tag-transform translate-and-add inner-vlan 503 inner-priority 0 rx-cttr 6 tx-cttr 6&lt;br/&gt;service-port vlan 222 gpon 0/1/0 ont 0 gemport 2 multi-service user-vlan 14 tag-transform translate-and-add inner-vlan 504 inner-priority 0 rx-cttr 6 tx-cttr 6&lt;br/&gt;save&lt;br/&gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&amp;gt;&lt;br/&gt;维护类操作：&lt;br/&gt;查看设备单板状态：&lt;br/&gt;display board 0&lt;br/&gt;&amp;nbsp; -------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; SlotID&amp;nbsp; BoardName&amp;nbsp; Status&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; SubType0 SubType1&amp;nbsp;&amp;nbsp;&amp;nbsp; Online/Offline&lt;br/&gt;&amp;nbsp; -------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H802EPBC&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //EPBC单板，默认为4个端口，从0-3&lt;br/&gt;&amp;nbsp; 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801EPBA&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //EPBA单板，默认为4个端口，从0-3&lt;br/&gt;&amp;nbsp; 3&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H802GPBD&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //GPBD单板，默认为8个端口，从0-7&lt;br/&gt;&amp;nbsp; 4&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801GPBC&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //GPBC单板，默认为8个端口，从0-7&lt;br/&gt;&amp;nbsp; 5&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 6&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 7&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801SCUL&amp;nbsp;&amp;nbsp; Active_normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //SCUL主控板，管理控制系统的运行。配置信息都保存在此板中&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 8&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801SCUL&amp;nbsp;&amp;nbsp; Standby_normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //SCUL为主备用，一般设备都带2块SCUL板&lt;br/&gt;&amp;nbsp; 9&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 10&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 11&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 12&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 13&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 14&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 15&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 16&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 17&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801GICF&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //OLT的千兆口上行板GICF，带2个GE 光口,端口0-1&lt;br/&gt;&amp;nbsp; 18&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; H801X2CA&amp;nbsp;&amp;nbsp; Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //OLT的万兆口上行板X2CA，带2个10GE光口,端口0-1&lt;br/&gt;&amp;nbsp; 19&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 20&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; -------------------------------------------------------------------------&lt;br/&gt;//查看设备端口状态&lt;br/&gt;display board 0/1&lt;br/&gt;&amp;nbsp; ---------------------------------------&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; Board Name&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : H802EPBC&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; Board Status&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ---------------------------------------&lt;br/&gt;&amp;nbsp; ------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; Port&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Port type&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 3&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ------------------------------------------&lt;br/&gt;&amp;nbsp; ------------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; F/S/P&amp;nbsp;&amp;nbsp;&amp;nbsp; ONT-ID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; MAC&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Control&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Run&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Config&amp;nbsp;&amp;nbsp;&amp;nbsp; Match&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; flag&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; state&amp;nbsp;&amp;nbsp; state&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; state&lt;br/&gt;&amp;nbsp; ------------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; 0/13/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1&amp;nbsp;&amp;nbsp; 0025-9E09-84F1&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp; //正常的设备状态.&lt;br/&gt;&amp;nbsp; 0/13/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 2&amp;nbsp;&amp;nbsp; 0025-9E09-8C03&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 3&amp;nbsp;&amp;nbsp; 0025-9E09-8B6B&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 4&amp;nbsp;&amp;nbsp; 0025-9E09-8C07&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 5&amp;nbsp;&amp;nbsp; 0025-9E09-8A47&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 6&amp;nbsp;&amp;nbsp; 0025-9E09-8B43&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; ------------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; In port 0, the total of ONTs are: 6&lt;br/&gt;&amp;nbsp; ------------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; F/S/P&amp;nbsp;&amp;nbsp;&amp;nbsp; ONT-ID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; MAC&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Control&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Run&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Config&amp;nbsp;&amp;nbsp;&amp;nbsp; Match&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; flag&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; state&amp;nbsp;&amp;nbsp; state&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; state&lt;br/&gt;&amp;nbsp; ------------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1&amp;nbsp;&amp;nbsp; 0025-9E89-E637&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 2&amp;nbsp;&amp;nbsp; 0025-9E50-56D7&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 3&amp;nbsp;&amp;nbsp; 0025-9E78-37F8&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; down&amp;nbsp;&amp;nbsp;&amp;nbsp; initial&amp;nbsp;&amp;nbsp; initial&amp;nbsp; //故障的设备状态.&lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 4&amp;nbsp;&amp;nbsp; 0025-9E50-56CF&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; down&amp;nbsp;&amp;nbsp;&amp;nbsp; initial&amp;nbsp;&amp;nbsp; initial&lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 5&amp;nbsp;&amp;nbsp; 0025-9E89-E63D&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; down&amp;nbsp;&amp;nbsp;&amp;nbsp; initial&amp;nbsp;&amp;nbsp; initial&lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 6&amp;nbsp;&amp;nbsp; 0025-9E09-6859&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; 0/13/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 7&amp;nbsp;&amp;nbsp; 0025-9E50-56AB&amp;nbsp;&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp; &lt;br/&gt;&amp;nbsp; ------------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; In port 1, the total of ONTs are: 7&lt;br/&gt;&amp;nbsp; In port 2, the total of ONTs are: 0&lt;br/&gt;&amp;nbsp; In port 3, the total of ONTs are: 0&lt;br/&gt;//有故障的设备,引起故障的原因可能是因为光路不通,或者设备掉电与设备故障.需要根据实际情况排查.&lt;br/&gt;//ONU通过单芯联到分光器,再通过分光器联结至OLT的PON口,通过MAC地址注册到OLT.通过各PON口下的ONU ID识别区分.&lt;br/&gt;//查看全局配置命令,也可以通过匹配符或者section细节查看具体配置信息&lt;br/&gt;display current-configuration&lt;/p&gt;&lt;p&gt;//匹配符| 后面通过 include 匹配字母,列出配置信息:&lt;br/&gt;display current-configuration | include vlan&lt;/p&gt;&lt;p&gt;//section细节比较具体.OLT配置信息分以下几个细节:&lt;br/&gt;&amp;lt;global-config&amp;gt;&amp;nbsp; 全球配置信息,包括设备的命名,添加的用户帐户信息.各种能力集配置信息,以及线路参数全局配置等.&lt;br/&gt;&amp;lt;device-config&amp;gt; 设备单板信息,槽位号,单板名称.&lt;br/&gt;&amp;lt;public-config&amp;gt; 设备的SNMP参数设置&lt;br/&gt;&amp;lt;vlan-config&amp;gt;,&amp;lt;vlanif10&amp;gt;,&amp;lt;vlanif99&amp;gt; 设备的vlan配置,以及透传的上行口,各vlan子接口所设置的地址参数.&lt;br/&gt;&amp;lt;epon&amp;gt;,&amp;lt;epon-0/1&amp;gt;,&amp;lt;epon-0/2&amp;gt;... 设备各单板配置的ONU数据信息.&lt;br/&gt;包括注册的MAC地址,分配的ONU ID,采用的线路模板,设备管理地址,管理vlan等.&lt;br/&gt;&amp;lt;platform-config&amp;gt; 主要是配置的保存参数&lt;br/&gt;&amp;lt;emu-config&amp;gt; 配置的电源参数&lt;br/&gt;&amp;lt;fan-0&amp;gt; 配置的风扇参数&lt;br/&gt;&amp;lt;autobackup-config&amp;gt; 配置的自动备份参数&lt;br/&gt;&amp;lt;bbs-config&amp;gt; 添加的pvc信息&lt;br/&gt;&amp;lt;meth0&amp;gt; 设备维护网口的配置信息&lt;br/&gt;&amp;lt;aaa&amp;gt; 设备设置的安全参数&lt;br/&gt;&amp;lt;post-system&amp;gt; 设备配置中的路由参数,以及允许访问的用户帐户&lt;/p&gt;&lt;p&gt;//举例,查看配置中所有的vlan配置细节.&lt;br/&gt;display current-configuration section vlan&lt;/p&gt;&lt;p&gt;//进入EPON单板,查看设备注册的情况&lt;br/&gt;interface epon 0/1&lt;br/&gt;display ont info 0 1&lt;br/&gt;&amp;nbsp; ---------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; F/S/P&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0/1/0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //设备机框/槽位/端口&lt;br/&gt;&amp;nbsp; ONT-ID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //ONU注册到OLT,分配的ONU ID. 为开局手动添加的.&lt;br/&gt;&amp;nbsp; Control flag&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //配置状态,激活可用.&lt;br/&gt;&amp;nbsp; Run state&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : down&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; // 设备状态 离线. 原因可能为光路不通,或者设备down机&lt;br/&gt;&amp;nbsp; Config state&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : initial&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //配置状态为 初始状态(initial),待设备上线之后方能正常.&lt;br/&gt;&amp;nbsp; Match state&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : initial&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //配置状态为 初始状态(initial)&lt;br/&gt;&amp;nbsp; ONT LLID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : -&lt;br/&gt;&amp;nbsp; Authentic type&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : MAC-auth&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //认证方式(即注册到OLT的方式),通过MAC地址注册.&lt;br/&gt;&amp;nbsp; MAC&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 0025-9E8E-90AA&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //上报的MAC地址信息.&lt;br/&gt;&amp;nbsp; Management mode&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : SNMP&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //对于MA561X和 MA562X,都是通过SNMP管理方式实现OLT对ONU的管理.&lt;br/&gt;&amp;nbsp; Multicast mode&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : CTC&lt;br/&gt;&amp;nbsp; SNMP profile ID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 1&lt;br/&gt;&amp;nbsp; SNMP profile name&amp;nbsp;&amp;nbsp;&amp;nbsp; : MDU&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //ONU采用的SNMP模板名称.&lt;br/&gt;&amp;nbsp; Description&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 603-2_TZJY-3#1DY-F7-MA5620&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //设备描述,手动添加的部分.&lt;br/&gt;&amp;nbsp; Last down cause&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : dying-gasp&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //最后一次离线原因.&lt;br/&gt;&amp;nbsp; Last up time&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 2010-03-24 17:11:14&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //最后一次上线时间&lt;br/&gt;&amp;nbsp; Last down time&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 2010-03-28 08:52:14&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //最后一次下线时间&lt;br/&gt;&amp;nbsp; Last dying gasp time : 2010-03-28 08:52:14&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //最后一次dying gasp时间&lt;br/&gt;&amp;nbsp; ---------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; Line profile ID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //所采用的线路模板编号&lt;br/&gt;&amp;nbsp; Line profile name&amp;nbsp;&amp;nbsp;&amp;nbsp; : MDU&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //所采用的线路模板名称&lt;br/&gt;&amp;nbsp; ---------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; FEC switch&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; :Disable&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //FEC开关关闭状态.&lt;br/&gt;&amp;nbsp; Encrypt type&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; :off&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //加密类型&lt;br/&gt;&amp;nbsp; DBA Profile-ID&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; :9&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //采用的DBA模板编号.9为系统自带的模板.&lt;br/&gt;&amp;nbsp; Traffic-table-index :6&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //采用的流量控制模板索引.6一般为不限速流量控制&lt;br/&gt;&amp;nbsp; Dba-threshold&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; :&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //DBA序列,暂无实际意义.&lt;br/&gt;&amp;nbsp; ---------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; Queue-set-index&amp;nbsp; Q1&amp;nbsp;&amp;nbsp;&amp;nbsp; Q2&amp;nbsp;&amp;nbsp;&amp;nbsp; Q3&amp;nbsp;&amp;nbsp;&amp;nbsp; Q4&amp;nbsp;&amp;nbsp;&amp;nbsp; Q5&amp;nbsp;&amp;nbsp;&amp;nbsp; Q6&amp;nbsp;&amp;nbsp;&amp;nbsp; Q7&amp;nbsp;&amp;nbsp;&amp;nbsp; Q8&lt;br/&gt;&amp;nbsp; ---------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; 3&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ---------------------------------------------------------------------&lt;br/&gt;//查看用户mac地址上报情况.&lt;br/&gt;display mac-address all&lt;br/&gt;//查看vlan XXX下学习到的地址信息,对于断定ONU用户故障,一般不要采用此方法.会查不出来.&lt;br/&gt;display mac-address vlan XXX.&lt;br/&gt;//而应该采用查询端口下MAC地址学习情况,需要知道用户所在ONU具体注册的PON口信息.&lt;br/&gt;display mac-address&amp;nbsp; port&amp;nbsp; 0/1/0&lt;/p&gt;&lt;p&gt;//对于配置错误的onu,如何添加删除或者更改配置资料,可以参考以下命令.&lt;br/&gt;1.因为ONU故障,用其他相同设备类型的ONU替换.通过自动发现命令,查看新上报的ONU 地址信息.按:&lt;br/&gt;display ont autofind all&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //目的:记录新的ONU 的MAC地址 1111-1111-1111&lt;br/&gt;进入待替换的故障ONU所注册的单板&lt;br/&gt;interface epon 0/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //此处可以通过查看PON口下设备状态来获取需要替换的ONU ID.假设故障设备位于2端口,ID为6&lt;br/&gt;ont modify 2 6 mac 1111-1111-1111&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //替换设备.&lt;br/&gt;结束后需要通过旧的管理地址(管理地址不变)登陆到设备中,补全设备信息.添加业务数据.结果注意保存(OLT上以及ONU上的)&lt;br/&gt;2.因为设备迁移,设备所注册的PON口有变,则旧数据需要删除,重新添加到新上报的端口中.&lt;br/&gt;&amp;nbsp; MAC地址在OLT内不可冲突,否则添加不成功;因此需要删除与设备端口ID有关的相关配置,再进行添加操作.&lt;br/&gt;&amp;nbsp; 需要查询到此设备MAC地址原有的注册端口和ONU ID,删除与此有关的所有信息(包括pvc和原有PON口下的ONU ID信息)&lt;br/&gt;&amp;nbsp; &lt;br/&gt;&amp;nbsp; 假设已知设备原来注册端口为 0/2/2, ONU ID 为6&amp;nbsp; 首先查询pvc信息.&lt;br/&gt;&amp;nbsp; display service-port port 0/2/2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //查看0/2/2 ID为6的所有pvc id&lt;br/&gt;&amp;nbsp;----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; INDEX VLAN VLAN&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; PORT F/ S/ P VPI&amp;nbsp; VCI&amp;nbsp; FLOW&amp;nbsp; FLOW&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; RX&amp;nbsp;&amp;nbsp; TX&amp;nbsp;&amp;nbsp; STATE&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; ID&amp;nbsp;&amp;nbsp; ATTR&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; TYPE&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; TYPE&amp;nbsp; PARA&lt;br/&gt;&amp;nbsp; ----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 8&amp;nbsp;&amp;nbsp; 99 common&amp;nbsp;&amp;nbsp; epon 0/2 /1&amp;nbsp; 3&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; vlan&amp;nbsp; 99&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; down&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 9&amp;nbsp;&amp;nbsp; 99 common&amp;nbsp;&amp;nbsp; epon 0/2 /1&amp;nbsp; 4&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; vlan&amp;nbsp; 99&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; up&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 10&amp;nbsp;&amp;nbsp; 99 common&amp;nbsp;&amp;nbsp; epon 0/2 /2&amp;nbsp; 5&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; vlan&amp;nbsp; 99&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; up&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 11&amp;nbsp;&amp;nbsp; 99 common&amp;nbsp;&amp;nbsp; epon 0/2 /2&amp;nbsp; 6&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; vlan&amp;nbsp; 99&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; down&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 12&amp;nbsp;&amp;nbsp; 99 common&amp;nbsp;&amp;nbsp; epon 0/2 /2&amp;nbsp; 7&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; vlan&amp;nbsp; 99&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; -&amp;nbsp;&amp;nbsp;&amp;nbsp; up&lt;br/&gt;undo service-port 11&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //需要将所有与0/2/2 onu id为6的pvc信息都删除,否则无法执行后面的操作.&lt;br/&gt;interface epon 0/2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; // 进入原来注册的PON口下&lt;br/&gt;ont delete 2 6&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; // 删除ONU注册信息.&lt;br/&gt;interface epon 0/1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; //进入新的pon口下,添加ONU信息(略)&lt;br/&gt;service-port vlan 99 epon 0/1/0 ont 1 multi-service user-vlan 99&amp;nbsp;&amp;nbsp;&amp;nbsp; //添加新的pvc信息.&lt;br/&gt;保存数据,至此设备添加完毕.登陆到设备上去,添加新的业务数据.&lt;/p&gt;&lt;p&gt;一、 设备数据配置及查询&lt;br/&gt;查看10槽位EPON板配置&lt;br/&gt;MA5680T(config)#display current-configuration section epon-0/10&lt;br/&gt;{ &amp;lt;cr&amp;gt;||&amp;lt;K&amp;gt; }:&lt;br/&gt;&amp;nbsp; Command:&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; display current-configuration section epon-0/10&lt;br/&gt;[MA5600V800R105: 5033]&lt;br/&gt;#&lt;br/&gt;[epon]&lt;br/&gt;&amp;nbsp; &amp;lt;epon-0/10&amp;gt;&lt;br/&gt;&amp;nbsp;interface epon 0/10&lt;br/&gt;&amp;nbsp;port 0 ont-auto-find enable&lt;br/&gt;&amp;nbsp;ont add 0 0 mac-auth 0025-9E64-5C46 profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot; dba-profile 11&lt;br/&gt;&amp;nbsp;ont add 0 1 mac-auth 0025-9E64-5B43 profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont snmp 0 1 v1&amp;nbsp; &amp;quot;public&amp;quot; &amp;quot;private&amp;quot; 10.50.58.2 161 &amp;quot;huawei&amp;quot;&lt;br/&gt;&amp;nbsp;ont add 0 2 mac-auth 0025-9E62-7E0B profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot; dba-profile 11&lt;br/&gt;&amp;nbsp;ont snmp 0 2 v1&amp;nbsp; &amp;quot;public&amp;quot; &amp;quot;private&amp;quot; 10.50.58.2 161 &amp;quot;huawei&amp;quot;&lt;br/&gt;&amp;nbsp;ont add 0 3 mac-auth 0025-9E8D-F5ED profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont add 0 4 mac-auth 0025-9E8D-F5A8 profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont add 0 5 mac-auth 0025-9E8D-F5C9 profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont ipconfig 0 0 ip-address 10.50.234.66 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;ont ipconfig 0 1 ip-address 10.50.234.67 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;ont ipconfig 0 2 ip-address 10.50.234.68 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;ont ipconfig 0 3 ip-address 10.50.234.74 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;ont ipconfig 0 4 ip-address 10.50.234.75 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;ont ipconfig 0 5 ip-address 10.50.234.76 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;port 1 ont-auto-find enable&lt;br/&gt;&amp;nbsp;ont add 1 0 mac-auth 0025-9E8E-7969 profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont ipconfig 1 0 ip-address 10.50.234.70 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;port 2 ont-auto-find enable&lt;br/&gt;&amp;nbsp;ont add 2 1 mac-auth 0018-82EB-3814 profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont add 2 2 mac-auth 0018-82E7-002B profile-id 12 desc &amp;quot;ONT_NO_DESCRIPTION&amp;quot;&lt;br/&gt;&amp;nbsp;ont ipconfig 2 1 ip-address 10.50.234.72 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;ont ipconfig 2 2 ip-address 10.50.234.73 mask 255.255.255.0 gateway 10.50.234.1 manage-vlan 3334&lt;br/&gt;&amp;nbsp;port 3 ont-auto-find enable&lt;br/&gt;#&lt;br/&gt;return&lt;br/&gt;MA5680T(config)#&lt;/p&gt;&lt;p&gt;查看10槽位下ONU&lt;br/&gt;MA5680T(config)#display board 0/10&lt;br/&gt;&amp;nbsp; ---------------------------------------&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; Board Name&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : H801EPBA&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; Board Status&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; : Normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ---------------------------------------&lt;br/&gt;&amp;nbsp; ------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp; Port&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Port type&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ------------------------------------------&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 0&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 1&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 2&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 3&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; EPON&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; ------------------------------------------&lt;br/&gt;&amp;nbsp; -----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; F/S/P&amp;nbsp; ONT-ID&amp;nbsp;&amp;nbsp;&amp;nbsp; MAC&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Control&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Run&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Config&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Match&amp;nbsp;&amp;nbsp;&amp;nbsp; Loopback&lt;br/&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Flag&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; State&amp;nbsp;&amp;nbsp;&amp;nbsp; State&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; State&amp;nbsp;&amp;nbsp;&amp;nbsp; State&amp;nbsp;&amp;nbsp; &lt;br/&gt;&amp;nbsp; -----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; 0/10/0&amp;nbsp;&amp;nbsp; 0 0025-9E64-5C46&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp;&amp;nbsp; disable&lt;br/&gt;&amp;nbsp; 0/10/0&amp;nbsp;&amp;nbsp; 1 0025-9E64-5B43&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp;&amp;nbsp; disable&lt;br/&gt;&amp;nbsp; 0/10/0&amp;nbsp;&amp;nbsp; 2 0025-9E62-7E0B&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp;&amp;nbsp; disable&lt;br/&gt;&amp;nbsp; 0/10/0&amp;nbsp;&amp;nbsp; 3 0025-9E8D-F5ED&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp;&amp;nbsp; disable&lt;br/&gt;&amp;nbsp; 0/10/0&amp;nbsp;&amp;nbsp; 4 0025-9E8D-F5A8&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp;&amp;nbsp; disable&lt;br/&gt;&amp;nbsp; 0/10/0&amp;nbsp;&amp;nbsp; 5 0025-9E8D-F5C9&amp;nbsp; active&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; up&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; normal&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; match&amp;nbsp;&amp;nbsp;&amp;nbsp; disable&lt;br/&gt;&amp;nbsp; -----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; In port 0, the total of ONTs are: 6&lt;br/&gt;&amp;nbsp; -----------------------------------------------------------------------------&lt;br/&gt;&amp;nbsp; F/S/P&amp;nbsp; ONT-ID&amp;nbsp;&amp;nbsp;&amp;nbsp; MAC&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Control&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Run&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Config&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; Match&amp;nbsp;&amp;nbsp;&amp;nbsp; Loopback&lt;br/&gt;&amp;nbsp;&amp;amp;nb&lt;/p&gt;&lt;p&gt;&lt;/p&gt;</description><pubDate>Sat, 15 Oct 2016 15:16:43 +0800</pubDate></item><item><title>OLT至ONU之间的最大传输距离超过了怎么办？</title><link>http://www.yyk8.cn/?id=44</link><description>&lt;p&gt;&amp;nbsp;用这个命令，端口上默认测距是0-20公里，可以改为20-40公里，但光功率预算要在范围之内&lt;br/&gt;&lt;br/&gt;MA5680T(config-if-gpon-0/1)#port 
1 range min-distance 20 max-distance 
40&lt;br/&gt;&lt;br/&gt;（最小测距和最大测距差值小于等于20KM）这样的话，最远测距是40KM，超出理论的20KM!这样做的话超出20KM的ONU还能上线。&lt;/p&gt;</description><pubDate>Thu, 22 Sep 2016 09:04:56 +0800</pubDate></item><item><title>贝尔吉比特I-120E破解超级帐号密码</title><link>http://www.yyk8.cn/?id=42</link><description>用普通账号登录后在浏览器输入192.168.1.1/backupsettings.conf，下载backupsettings.conf这个文件，用记事本打开，查找“AdminUserName”得到密码串：后面的就是账号和密码。</description><pubDate>Sun, 13 Dec 2015 22:07:48 +0800</pubDate></item><item><title>关于路由器PING不通OLT的问题！</title><link>http://www.yyk8.cn/?id=41</link><description>&lt;p&gt;几个月来的问题，终于在刚刚解决了，一直一来我的路由器都PING不通OLT，但这并不影响我使用，前几天看过人家的OLT都没有问题。&lt;/p&gt;&lt;p&gt;由于带的有用户，所以每次只能在晚上尝试，今天终于成功，把最终方法分享到这里！&lt;/p&gt;&lt;p&gt;路由器里的相关设置:&lt;/p&gt;&lt;p&gt;添加管理VLAN比如VLAN100并映射到LAN口上，设置IP192.168.0.1掩码255.255.255.0&lt;/p&gt;&lt;p&gt;把LAN地址也设置成为192.168.0.1&lt;/p&gt;&lt;p&gt;OLT设置&lt;/p&gt;&lt;p&gt;interface vlanif 100 &amp;nbsp; &amp;nbsp; //添加VLAN100&lt;br/&gt;&lt;/p&gt;&lt;p&gt;ip address 192.168.0.2 255.255.255.0 &amp;nbsp;//设置管理IP&lt;/p&gt;&lt;p&gt;&lt;br/&gt;&lt;/p&gt;&lt;p&gt;然后就可以PING通了！&lt;/p&gt;&lt;p&gt;&lt;br/&gt;&lt;/p&gt;</description><pubDate>Wed, 02 Dec 2015 01:22:12 +0800</pubDate></item><item><title>天猫魔盒升级后不能用了怎么办？</title><link>http://www.yyk8.cn/?id=40</link><description>&lt;p style=&quot;text-align: left; text-indent: 2em;&quot;&gt;&amp;nbsp; &amp;nbsp;&amp;nbsp;广电总局出手了，盒子不能看了，怎么办？天猫魔盒升级后所有的APP都删除了，不过没有关系，下面这些软件还能看直播和视频，电视猫、CIBN优酷、爱奇艺荔枝、华数、芒果、CIN高清影视、电视应用精选　　所以，大家也不要惊慌，下面告诉大家天猫魔盒升级后自动删除软件的有效解决办法。&lt;/p&gt;&lt;p style=&quot;border: 0px; margin-top: 0px; margin-bottom: 0px; padding: 26px 0px 0px; word-wrap: break-word; line-height: 26px; white-space: normal; text-align: left; text-indent: 2em; background-color: rgb(255, 255, 255);&quot;&gt;&lt;strong style=&quot;border: 0px; margin: 0px; padding: 0px;&quot;&gt;解决方法：&lt;/strong&gt;&lt;/p&gt;&lt;p style=&quot;border: 0px; margin-top: 0px; margin-bottom: 0px; padding: 26px 0px 0px; word-wrap: break-word; line-height: 26px; white-space: normal; text-align: left; text-indent: 2em; background-color: rgb(255, 255, 255);&quot;&gt;　　在你的天猫魔盒上安装【电视应用精选】什么问题都不是问题，让你再也不用担心！看直播看点播，看看看！芒果TV、CIBN高清影视、华数TV、虎牙直播、爱奇艺视频.....到目前为止，免阿里云yunos删除，实时更新，有你所要，下你所想！&lt;/p&gt;&lt;p&gt;　　【电视应用精选】安装包下载：&lt;a href=&quot;http://pan.baidu.com/s/1kTEn2Qj&quot; target=&quot;_blank&quot;&gt;http://pan.baidu.com/s/1kTEn2Qj&lt;/a&gt;　　应用截图：　　&lt;/p&gt;&lt;p&gt;　　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_3.jpeg&quot;/&gt;　　&lt;/p&gt;&lt;p&gt;&lt;strong style=&quot;border: 0px; margin: 0px; padding: 0px;&quot;&gt;安装教程：&lt;/strong&gt;　　1：将U盘插到盒子的USB接口上面，检测到外接设备，选择“应用”并打开&lt;/p&gt;&lt;p&gt;　　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_4.png&quot;/&gt;　　&lt;/p&gt;&lt;p&gt;如果没有弹出对话框，打开我的应用，选择「多媒体播放」，找到U盘设备，打开“装应用”&lt;/p&gt;&lt;p&gt;　　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_5.jpeg&quot;/&gt;　&lt;/p&gt;&lt;p&gt;　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_6.jpeg&quot;/&gt;　&lt;/p&gt;&lt;p&gt;　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_7.jpeg&quot;/&gt;　&lt;/p&gt;&lt;p&gt;　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_8.jpeg&quot;/&gt;　&lt;/p&gt;&lt;p&gt;　2、找到【电视应用精选】apk并选择，按「确定」即可安装啦&lt;/p&gt;&lt;p&gt;　　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_9.jpeg&quot;/&gt;　&lt;/p&gt;&lt;p&gt;　3、安装完“电视应用精选”之后，我们就可以在里面下载我们需要的软件，例如电视猫、CIBN优酷、爱奇艺荔枝 华数 芒果 CINB高清影视等。　　&lt;img src=&quot;http://photocdn.sohu.com/20151116/mp42094702_1447666954311_10.jpeg&quot;/&gt;&lt;/p&gt;</description><pubDate>Thu, 19 Nov 2015 13:08:28 +0800</pubDate></item><item><title>新世界UO服务器脚本下载！</title><link>http://www.yyk8.cn/?id=39</link><description>&lt;p&gt;经过几天的学习和努力，终于把新世界UO站配制完成，现在把服务器脚本提供给大家，配合本站客户端使用!&lt;/p&gt;&lt;p&gt;现在简单说一下架设方法，把SPHERE文件夹放在D盘根目录下，本站的UO客户端文件夹也要放在D盘根目录下，如有改动请在sphere.ini文件里面修改，然后直接运行SphereSvr.exe就可以了，GM帐号yyk密码yyk.ren 里面自带axis天神之手管理工具！&lt;/p&gt;&lt;p&gt;下载地址：&lt;/p&gt;&lt;p&gt;百度网盘：&lt;a href=&quot;http://pan.baidu.com/s/1i3Cn4NV&quot; target=&quot;_blank&quot;&gt;http://pan.baidu.com/s/1i3Cn4NV&lt;/a&gt;&lt;/p&gt;&lt;p&gt;360云盘：&lt;a href=&quot;http://yunpan.cn/cFraZbuyfKHsY&quot; target=&quot;_blank&quot;&gt;http://yunpan.cn/cFraZbuyfKHsY&lt;/a&gt; &amp;nbsp;访问密码 bd46&lt;/p&gt;</description><pubDate>Tue, 20 Oct 2015 00:18:28 +0800</pubDate></item></channel></rss>