一个B类地址的子网掩码为255. 255. 240. 0......

若: 您要划分的IP地址是：172.016.000.000 是 B 类IP地址
子网掩码是：255.255.240.000
则 您要划分的子网数量是 16 个，
每段子网的网络号是TO前IP的最后一位减1
每段子网的广播地址是TO后IP最后一位加+1
1> 172.016.0.1 TO 172.016.15.254
2> 172.016.16.1 TO 172.016.31.254
3> 172.016.32.1 TO 172.016.47.254
4> 172.016.48.1 TO 172.016.63.254
5> 172.016.64.1 TO 172.016.79.254
6> 172.016.80.1 TO 172.016.95.254
7> 172.016.96.1 TO 172.016.111.254
8> 172.016.112.1 TO 172.016.127.254
9> 172.016.128.1 TO 172.016.143.254
10> 172.016.144.1 TO 172.016.159.254
11> 172.016.160.1 TO 172.016.175.254
12> 172.016.176.1 TO 172.016.191.254
13> 172.016.192.1 TO 172.016.207.254
14> 172.016.208.1 TO 172.016.223.254
15> 172.016.224.1 TO 172.016.239.254
16> 172.016.240.1 TO 172.016.255.254

每个子网可用的最大IP地址数 为4094

256-240=16
256/16=16
算出子网数为16
主机位为12.2的12次方-2=4094
每个子网最大可用IP数为4094个

什么东西啊