IPv4
Default Route:
0.0.0.0/0
Reserved & Special use Ranges:
0.0.0.0/8 – “This” Network (RFC 1122)
10.0.0.0/8 – Private-Use Networks (also in RFC 1918)
127.0.0.0/8 – Loopback (RFC 1122)
169.254.0.0/16 – Automatic Private IP Addressing APIPA (RFC 3927)
172.16.0.0/12 – Private IP Range (also in RFC 1918)
192.0.0.0/24 – IETF Protocol Assignments (RFC 5736)
192.0.2.0/24 – TEST-NET-1 (RFC 5737)
192.88.99.0/24 – 6to4 Relay Anycast (RFC 3068)
192.168.0.0/16 – Private IP Range (also in RFC 1918)
198.18.0.0/15 – Network Interconnect Device Benchmark Testing (RFC 2544)
198.51.100.0/24 – TEST-NET-2 (RFC 5737)
203.0.113.0/24 – TEST-NET-3 (RFC 5737)
224.0.0.0/4 – Multicast (RFC 3171)
240.0.0.0/4 – Reserved (RFC 1112)
255.255.255.255/32 – Limited Broadcast (RFC 919 & RFC 922)
Most likely never get used:
240.0.0.0 – 255.255.255.254
IPv6
Default Route:
::/0
Loopback:
::1
Unspecified:
::
Reserved & Special use Ranges:
0000::/8 – Reserved (RFC 4291)
0064:FF9B::/96 NAT64 (RFC 6052)
0100::/8 – Reserved “Discard-Only” (RFC 4291)
0200::/7 – Reserved (former “OSI NSAP”) (RFC 4048)
0400::/6 – Reserved (RFC 4291)
0800::/5 – Reserved (RFC 4291)
1000::/4 – Reserved (RFC 4291)
2000::/3 – Global Unicast (RFC 4291)
4000::/3 – Reserved (RFC 4291)
6000::/3 – Reserved (RFC 4291)
8000::/3 – Reserved (RFC 4291)
a000::/3 – Reserved (RFC 4291)
c000::/3 – Reserved (RFC 4291)
e000::/4 – Reserved (RFC 4291)
f000::/5 – Reserved (RFC 4291)
f800::/6 – Reserved (RFC 4291)
fc00::/7 – Unique Local Unicast (RFC 4193)
fe00::/9 – Reserved (RFC 4291)
fe80::/10 – Link-Scoped Unicast (RFC 4291)
fec0::/10 – Reserved (former “Site Local”, no longer Used) (RFC 3879)
ff00::/8 – Multicast (RFC 4291)
Other known Ranges:
2002::/16 (6t4 Tunnels)
2001::/32 Terdero (RFC 4380)
How big is 2000::/3?
2000:0000:0000:0000:0000:0000:0000:0000
till
3FFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF