曾经以为保留地址下面三类.原来使用中还有很多的.
A类 10.0.0.0--10.255.255.255
B类 172.16.0.0--172.31.255.255
C类 192.168.0.0--192.168.255.255
Address Block Name RFC
0.0.0.0/8 "This host on this network" [RFC1122], section 3.2.1.3
10.0.0.0/8 Private-Use [RFC1918]
100.64.0.0/10 Shared Address Space [RFC6598]
127.0.0.0/8 Loopback [RFC1122], section 3.2.1.3
169.254.0.0/16 Link Local [RFC3927]
172.16.0.0/12 Private-Use [RFC1918]
192.0.0.0/24[2] IETF Protocol Assignments [RFC6890], section 2.1
192.0.0.0/29 IPv4 Service Continuity Prefix [RFC7335]
192.0.0.8/32 IPv4 dummy address [RFC7600]
192.0.0.9/32 Port Control Protocol Anycast [RFC-ietf-pcp-anycast-08]
192.0.0.170/32, 192.0.0.171/32 NAT64/DNS64 Discovery [RFC7050], section 2.2
192.0.2.0/24 Documentation (TEST-NET-1) [RFC5737]
192.31.196.0/24 AS112-v4 [RFC7535]
192.52.193.0/24 AMT [RFC7450]
192.88.99.0/24 Deprecated (6to4 Relay Anycast) [RFC7526]
192.168.0.0/16 Private-Use [RFC1918]
192.175.48.0/24 Direct Delegation AS112 Service [RFC7534]
198.18.0.0/15 Benchmarking [RFC2544]
198.51.100.0/24 Documentation (TEST-NET-2) [RFC5737]
203.0.113.0/24 Documentation (TEST-NET-3) [RFC5737]
240.0.0.0/4 Reserved [RFC1112], section 4
255.255.255.255/32 Limited Broadcast [RFC919], section 7
http://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml