问一些基础问题

朴朴

Question1：128.0.0.0和191.225.0.0，192.0.0.0，223.225.225.0作为保留IP，具体作何用途？
Question2：Rip v1在做路由汇总的时候，依据什么来汇总成A、B、C类地址？

kkingkill

Question1,请看RFC3330
  128.0.0.0/16 - This block, corresponding to the numerically lowest of
   the former Class B addresses, was initially and is still reserved by
   the IANA.  Given the present classless nature of the IP address
   space, the basis for the reservation no longer applies and addresses
   in this block are subject to future allocation to a Regional Internet
   Registry for assignment in the normal manner.

191.255.0.0/16 - This block, corresponding to the numerically highest
   to the former Class B addresses, was initially and is still reserved
   by the IANA.  Given the present classless nature of the IP address
   space, the basis for the reservation no longer applies and addresses
   in this block are subject to future allocation to a Regional Internet
   Registry for assignment in the normal manner.

192.0.0.0/24 - This block, corresponding to the numerically lowest of
   the former Class C addresses, was initially and is still reserved by
   the IANA.  Given the present classless nature of the IP address
   space, the basis for the reservation no longer applies and addresses
   in this block are subject to future allocation to a Regional Internet
   Registry for assignment in the normal manner.

223.255.255.0/24 - This block, corresponding to the numerically
   highest of the former Class C addresses, was initially and is still
   reserved by the IANA.  Given the present classless nature of the IP
   address space, the basis for the reservation no longer applies and
   addresses in this block are subject to future allocation to a
   Regional Internet Registry for assignment in the normal manner.

Question2：Rip v1在做路由汇总的时候，依据什么来汇总成A、B、C类地址？
     RIPV1自动汇总是不能关闭的，在网络边界会自动汇总

task

Question2：Rip v1在做路由汇总的时候，依据什么来汇总成A、B、C类地址？

首先RIPV1是有类路由协议，有类路由协议在发送路由更新的时候，不携带子网掩码。接收到路由更新的路由器，根据这个更新条目的IP地址，进行比较。如果此更新条目于收到此条目的接口的IP在同一个主网，那么就使用此接口的子网掩码。如果不在同一个子网，则将其划入默认的主网里，使用此主网所属的A类、B类、C类掩码。

Jeff.

回复 2# kkingkill


    专业....

Jeff.

回复 3# task


    task 最近学习长进了不少啊，可喜可贺！继续努力！

朴朴

厉害的可怕