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Peng Hailin 2016-08-31 10:49:04 +08:00
parent 8bdb6fbbc5
commit 3e5816f071
1 changed files with 10 additions and 9 deletions

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d05-IP-Addressing.md
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@ -503,16 +503,17 @@ C类地址 = 255.255.255.0
抱歉的是，计算出汇总路由（a summary route）的唯一方法是将IP地址转换成二进制形式。如你不这样做，就无法知道是否通告了正确的汇总路由，而这将导致网络故障。
首先，写出完整的所有网络地址，接着在右边写出其二进制形式，如下面所示。
| - | - |
| 网络号 | 二进制形式 |
| -- | -- |
| 172.16.8.0 | <b>10101100.00010000.00001</b>000.00000000 |
| 172.16.9.0 | <b>10101100.00010000.00001</b>001.00000000 |
| 172.16.10.0 | <b>10101100.00010000.00001</b>010.00000000 |
| 172.16.11.0 | <b>10101100.00010000.00001</b>011.00000000 |
| 172.16.12.0 | <b>10101100.00010000.00001</b>100.00000000 |
| 172.16.13.0 | <b>10101100.00010000.00001</b>101.00000000 |
| 172.16.14.0 | <b>10101100.00010000.00001</b>110.00000000 |
| 172.16.15.0 | <b>10101100.00010000.00001</b>111.00000000 |
| 172.16.8.0 | **10101100.00010000.00001**000.00000000 |
| 172.16.9.0 | **10101100.00010000.00001**001.00000000 |
| 172.16.10.0 | **10101100.00010000.00001**010.00000000 |
| 172.16.11.0 | **10101100.00010000.00001**011.00000000 |
| 172.16.12.0 | **10101100.00010000.00001**100.00000000 |
| 172.16.13.0 | **10101100.00010000.00001**101.00000000 |
| 172.16.14.0 | **10101100.00010000.00001**110.00000000 |
| 172.16.15.0 | **10101100.00010000.00001**111.00000000 |
| 匹配的位 | 10101100.0010000.00001 = 21位 |
我将每个网络地址中匹配的位进行了加粗。你可以看到各个网络地址的前21位是匹配的，所有汇总路由可由下面的21位反应出来。