Linux网络高手请来帮忙！

Question

我有个题目：
1, You are given the following information about a host IP:120.14.22.16
Suprenet mask:255.255.128.0
what are the network and hostID?

2, A network has been assigned the following range of IP address:68.171.64.0-68.171.79.225.
Provide the CIDR(Class Inter Domain Routing) address for the network.

Answer 1

一.ip地址与子网掩码都转换为二进制做与运算,得到的前24位即为Network ID,为120.14.0,Host ID就是16.

二.将所给IP划分在同一子网内，如果68.171.64.0可以作为子网地址，68.171.79.225作为广播地址的话，那么子网掩码可以设定为255.240.0.0，刚好可以容纳2^12-2=4094台主机。子网掩码中有12个“1”，即CIDR为68.171.64.0/12.

刚自学了一周，我自己做的答案不知道对不对，如有误，望高手更正赐教。

Answer 2

对的，只是网络问题，可变长子网掩码划分。