| Longueur CIDR | Masque | Nombre de réseaux | Hôtes | | ------------- | --------------- | ----------------- | ------------- | | /1 | 128.0.0.0 | 128 A | 2,147,483,392 | | /2 | 192.0.0.0 | 64 A | 1,073,741,696 | | /3 | 224.0.0.0 | 32 A | 536,870,848 | | /4 | 240.0.0.0 | 16 A | 268,435,424 | | /5 | 248.0.0.0 | 8 A | 134,217,712 | | /6 | 252.0.0.0 | 4 A | 67,108,856 | | /7 | 254.0.0.0 | 2 A | 33,554,428 | | /8 | 255.0.0.0 | 1 A | 16,777,214 | | /9 | 255.128.0.0 | 128 B | 8,388,352 | | /10 | 255.192.0.0 | 64 B | 4,194,176 | | /11 | 255.224.0.0 | 32 B | 2,097,088 | | /12 | 255.240.0.0 | 16 B | 1,048,544 | | /13 | 255.248.0.0 | 8 B | 524,272 | | /14 | 255.252.0.0 | 4 B | 262,136 | | /15 | 255.254.0.0 | 2 B | 131,068 | | /16 | 255.255.0.0 | 1 B | 65,534 | | /17 | 255.255.128.0 | 128 C | 32,512 | | /18 | 255.255.192.0 | 64 C | 16,256 | | /19 | 255.255.224.0 | 32 C | 8,128 | | /20 | 255.255.240.0 | 16 C | 4,064 | | /21 | 255.255.248.0 | 8 C | 2,032 | | /22 | 255.255.252.0 | 4 C | 1,016 | | /23 | 255.255.254.0 | 2 C | 508 | | /24 | 255.255.255.0 | 1 C | 254 | | /25 | 255.255.255.128 | 2 sous-réseaux | 124 | | /26 | 255.255.255.192 | 4 sous-réseaux | 62 | | /27 | 255.255.255.224 | 8 sous-réseaux | 30 | | /28 | 255.255.255.240 | 16 sous-réseaux | 14 | | /29 | 255.255.255.248 | 32 sous-réseaux | 6 | | /30 | 255.255.255.252 | 64 sous-réseaux | 2 | | /31 | 255.255.255.254 | Aucun | Aucun | | /32 | 255.255.255.255 | 1/256 C | 1 | --- ### Les classes non routables 10.0.0.0 à 10.255.255.255 (10.0.0.0/8) 172.16.0.0 à 172.31.255.255 (172.16.0.0/12) 192.168.0.0 à 192.168.255.255 (192.168.0.0/16) 127.0.0.0 à 127.255.255.255 (LoopBack 127.0.0.0/8) 169.254.0.0 à 169.254.255.255 (APIPA 169.254.0.0/16) 224.0.0.0 à 239.255.255.255 (Multicast 224.0.0.0/4) 100.64.0.0 à 100.127.255.255 (CGN RFC6598 100.64.0.0/10)