IPv4地址范围以及子网范围计算+子网掩码表

IPv4地址范围以及子网范围计算

1. 分类IP范围

Class	Range
A	0.0.0.0 - 10.255.255.255
B	128.0.0.0 - 191.255.255.255
C	192.0.0.0 - 223.255.255.255
D	224.0.0.0 - 239.255.255.255
E	240.0.0.0 - 255.255.255.255

2. 保留IP范围

10.0.0.0 - 10.255.255.255
127.0.0.0 - 127.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255

3. 子网范围计算

如：
1.1.1.101/28
/28表示前面28位的值为1，即 11111111 11111111 11111111 11110000
换算成10进制为 255.255.255.240
因此， /28 = 255.255.255.240 netmask

然后， 256 - 240 = 16, 即子网范围为16
1.1.1.0
1.1.1.16
1.1.1.32
… …

因此，1.1.1.101 位于 1.1.1.96 - 1.1.1.111

4. 子网掩码表

子网掩码位数	子网掩码	Hosts
/31	255.255.255.254	1 host
/30	255.255.255.252	2 hosts
/29	255.255.255.248	6 hosts
/28	255.255.255.240	14 hosts
/27	255.255.255.224	30 hosts
/26	255.255.255.192	62 hosts
/25	255.255.255.128	126 hosts
/24	255.255.255.0	254 hosts
/23	255.255.254.0	510 hosts
/22	255.255.252.0	1022 hosts
/21	255.255.248.0	2046 hosts
/20	255.255.240.0	4094 hosts
/19	255.255.224.0	8190 hosts
/18	255.255.192.0	16382 hosts
/17	255.255.128.0	32766 hosts
/16	255.255.0.0	65534 hosts
/15	255.254.0.0	131070 hosts
/14	255.252.0.0	262142 hosts
/13	255.248.0.0	524286 hosts
/12	255.240.0.0	1048574 hosts
/11	255.224.0.0	2097150 hosts
/10	255.192.0.0	4194302 hosts
/9	255.128.0.0	8388606 hosts
/8	255.0.0.0	16777214 hosts