CIDR的另一个好处就是可以进行前缀路由聚合。例如， 16个原来的C类（/24）网络现在可以聚合在一起，对外显示了一个/20的网络了（如果这些网络的的地址前20位都相同，见下红字部分）。两个对齐的/20网络又可进一步聚合为/19，依此类推。这有效地减少了要对外显示的网络数，防止了'路由表爆炸'，也遏制了互联网进一步扩大。
CIDR
| IP/CIDR |
Δ 与最后一个地址的差值 |
掩码 |
主机数 (*) |
类别 |
备注 |
@H_502[email protected]/32
@H_502_30@+0.0.0.0
@H_502[email protected]
@H_502_30@1
@H_502_30@1/256 C
@H_502_30@
@H_502[email protected]/31
@H_502_30@+0.0.0.1
@H_502[email protected]
@H_502_30@2
@H_502_30@1/128 C
@H_502_30@d = 0 ... (2n) ... 254
@H_502[email protected]/30
@H_502_30@+0.0.0.3
@H_502[email protected]
@H_502_30@4
@H_502_30@1/64 C
@H_502_30@d = 0 ... (4n) ... 252
@H_502[email protected]/29
@H_502_30@+0.0.0.7
@H_502[email protected]
@H_502_30@8
@H_502_30@1/32 C
@H_502_30@d = 0 ... (8n) ... 248
@H_502[email protected]/28
@H_502_30@+0.0.0.15
@H_502[email protected]
@H_502_30@16
@H_502_30@1/16 C
@H_502_30@d = 0 ... (16n) ... 240
@H_502[email protected]/27
@H_502_30@+0.0.0.31
@H_502[email protected]
@H_502_30@32
@H_502_30@1/8 C
@H_502_30@d = 0 ... (32n) ... 224
@H_502[email protected]/26
@H_502_30@+0.0.0.63
@H_502[email protected]
@H_502_30@64
@H_502_30@1/4 C
@H_502_30@d = 0,64,128,192
@H_502[email protected]/25
@H_502_30@+0.0.0.127
@H_502[email protected]
@H_502_30@128
@H_502_30@1/2 C
| 502[email protected]/24 |
@H_502_30@+0.0.0.255
@H_502[email protected]
@H_502_30@256
@H_502_30@1 C
@H_502[email protected]/23
@H_502_30@+0.0.1.255
@H_502[email protected]
@H_502_30@512
@H_502_30@2 C
@H_502_30@c = 0 ... (2n) ... 254
@H_502[email protected]/22
@H_502_30@+0.0.3.255
@H_502[email protected]
@H_502_30@1,024
@H_502_30@4 C
@H_502_30@c = 0 ... (4n) ... 252
@H_502[email protected]/21
@H_502_30@+0.0.7.255
@H_502[email protected]
@H_502_30@2,048
@H_502_30@8 C
@H_502_30@c = 0 ... (8n) ... 248
@H_502_30@a.b.c.0/20
@H_502_30@+0.0.15.255
@H_502_30@255.255.240.000
@H_502_30@4,096
@H_502_30@16 C
@H_502_30@c = 0 ... (16n) ... 240
@H_502[email protected]/19
@H_502_30@+0.0.31.255
@H_502[email protected]
@H_502_30@8,192
@H_502_30@32 C
@H_502_30@c = 0 ... (32n) ... 224
@H_502[email protected]/18
@H_502_30@+0.0.63.255
@H_502[email protected]
@H_502_30@16,384
@H_502_30@64 C
@H_502_30@c = 0,170); padding:0.2em 0.4em">a.b.c.0/17
@H_502_30@+0.0.127.255
@H_502[email protected]
@H_502_30@32,768
@H_502_30@128 C
@H_502[email protected]/16
@H_502_30@+0.0.255.255
@H_502[email protected]
@H_502_30@65,536
@H_502_30@256 C = 1 B
@H_502[email protected]/15
@H_502_30@+0.1.255.255
@H_502[email protected]
@H_502_30@131,072
@H_502_30@2 B
@H_502_30@b = 0 ... (2n) ... 254
@H_502[email protected]/14
@H_502_30@+0.3.255.255
@H_502[email protected]
@H_502_30@262,144
@H_502_30@4 B
@H_502_30@b = 0 ... (4n) ... 252
@H_502[email protected]/13
@H_502_30@+0.7.255.255
@H_502[email protected]
@H_502_30@524,288
@H_502_30@8 B
@H_502_30@b = 0 ... (8n) ... 248
@H_502[email protected]/12
@H_502_30@+0.15.255.255
@H_502[email protected]
| 502_30@16 B |
@H_502_30@b = 0 ... (16n) ... 240
@H_502[email protected]/11
@H_502_30@+0.31.255.255
@H_502[email protected]
| 502_30@32 B |
@H_502_30@b = 0 ... (32n) ... 224
@H_502[email protected]/10
@H_502_30@+0.63.255.255
@H_502[email protected]
@H_502_30@4,194,304
@H_502_30@64 B
@H_502_30@b = 0,170); padding:0.2em 0.4em">a.b.0.0/9
@H_502_30@+0.127.255.255
@H_502[email protected]
| 502_30@128 B |
@H_502[email protected]/8
@H_502_30@+0.255.255.255
@H_502[email protected]
502_30@256 B = 1 A |
@H_502[email protected]/7
@H_502_30@+1.255.255.255
@H_502[email protected]
@H_502_30@33,554,432
@H_502_30@2 A
@H_502_30@a = 0 ... (2n) ... 254
@H_502[email protected]/6
@H_502_30@+3.255.255.255
@H_502[email protected]
@H_502_30@67,108,864
@H_502_30@4 A
@H_502_30@a = 0 ... (4n) ... 252
@H_502[email protected]/5
@H_502_30@+7.255.255.255
@H_502[email protected]
@H_502_30@134,217,728
@H_502_30@8 A
@H_502_30@a = 0 ... (8n) ... 248
@H_502[email protected]/4
@H_502_30@+15.255.255.255
@H_502[email protected]
@H_502_30@268,435,456
@H_502_30@16 A
@H_502_30@a = 0 ... (16n) ... 240
@H_502[email protected]/3
@H_502_30@+31.255.255.255
@H_502[email protected]
@H_502_30@536,870,912
@H_502_30@32 A
@H_502_30@a = 0 ... (32n) ... 224
@H_502[email protected]/2
@H_502_30@+63.255.255.255
@H_502[email protected]
| 502_30@64 A |
@H_502_30@a = 0,170); padding:0.2em 0.4em">a.0.0.0/1
@H_502_30@+127.255.255.255
@H_502[email protected]
502_30@128 A |
@H_502[email protected]/0
@H_502_30@+255.255.255.255
@H_502[email protected]
502_30@256 A |
