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IPv4 and IPv6 Reference Guide

I have put this guide to Internet Protocol version 4 and version 6 together on a single page. This will help show the similarities and the differences in the protocols. This deals with addressing and subnetting for deployment rather than a detailed explanation. There are IPv4 and IPv6 Subnet Sheets one above the other.

IPv4 and IPv6 Address Space

IPv4 0.0.0.0 - 255.255.255.255

IPv6 0000:0000:0000:0000:0000:0000:0000:0000 - ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff

All IP addresses are allocated by Internet Assigned Numbers Authority (IANA) and the assignment of IPv4 address space. Blocks of this space is assigned to local internet registries for them to allocate to organisations or companies based on their local rules these are the Regional Internet Registries RIRs these are:

AFRINIC Africa Region
APNIC Asia/Pacific Region
ARIN Canada, USA, and some Caribbean Islands
LACNIC Latin America and some Caribbean Islands
RIPE NCC Europe, the Middle East, and Central Asia

Special Address Blocks

There are special allocations too. Request for Comment RFC-1918 are probably the most famous as a selection of addresses for private use:

Private IPv4 Networks

Address Range Use
10.0.0.0/8 10.0.0.0 - 10.255.255.255 Class A Private Addresses
172.16.0.0/12 172.16.0.0 - 172.31.255.255 Class B Private Addresses
192.168.0.0/16 192.168.0.0 - 192.168.255.255 Class C Private Addresses

Reserved IPv4 Networks

Address Range Use
0.0.0.0/8 0.0.0.0 - 0.255.255.255 Reserved for self-identification
127.0.0.0/8 127.0.0.0 - 127.255.255.255 Reserved for Loopback
169.254.0.0/16 169.254.0.0 - 169.254.255.255 Reserved for Link Local
224.0.0.0/4 224.0.0.0 - 239.255.255.255 Multicast
240.0.0.0/4 240.0.0.0 - 255.255.255.255 Future use

Reserved IPv6 Networks

Address Range Use
::1/128 0000:0000:0000:0000:0000:0000:0000:0001 - 0000:0000:0000:0000:0000:0000:0000:0001 Localhost
::ffff:0:0/96 0000:0000:0000:0000:0000:ffff:0000:0000 - 0000:0000:0000:0000:0000:ffff:ffff:ffff IPv4-mapped IPv6 address all IPv4
2002::/16 2002:0000:0000:0000:0000:0000:0000:0000 - 2002:ffff:ffff:ffff:ffff:ffff:ffff:ffff 6to4 Routing Prefix
fc00::/7 fc00:0000:0000:0000:0000:0000:0000:0000 - fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff Unique Local Address Private Addresses like RFC1918
fe80::/10 fe80:0000:0000:0000:0000:0000:0000:0000 - fe80:ffff:ffff:ffff:ffff:ffff:ffff:ffff Link Local None routable for adjacent devices
ff00::/8 ff00:0000:0000:0000:0000:0000:0000:0000 - ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff Multicast

Default Routes

Route Use
0.0.0.0/0 IPv4 Default Route
::/0 IPv6 Default Route

IPv4 and IPv6 Prefixes

Prefix Mask Use
/8 255.0.0.0 IPv4 Class A Network
/16 255.255.0.0 IPv4 Class B Network
/24 255.255.255.0 IPv4 Class C Network A "normal" Network and Smallest Internet Routable Block
/32 255.255.255.255 IPv4 Host Address
/32 IPv6 Internet Service Provider Allocation ISP
/48 IPv6 Smallest Internet Routable Block
/64 IPv6 A "normal" Network Residential Allocation
/128 IPv6 Host Address

IPv4 Full Subnet Mask Table

Bits Mask Inverse Mask Number of Hosts Number of Class Cs
/0 0.0.0.0 255.255.255.255 4,294,967,296 16,777,216
/1 128.0.0.0 127.255.255.255 2,147,483,648 8,388,608
/2 192.0.0.0 63.255.255.255 1,073,741,824 4,194,304
/3 224.0.0.0 31.255.255.255 536,870,912 2,097,152
/4 240.0.0.0 15.255.255.255 268,435,456 1,048,576
/5 248.0.0.0 7.255.255.255 13,4217,728 524,288
/6 252.0.0.0 3.255.255.255 6,7108,864 262,144
/7 254.0.0.0 1.255.255.255 3,3554,432 131,072
/8 255.0.0.0 0.255.255.255 1,6777,216 65,536
/9 255.128.0.0 0.127.255.255 8,388,608 32,768
/10 255.192.0.0 0.63.255.255 4,194,304 16,384
/11 255.224.0.0 0.31.255.255 2,097,152 8,192
/12 255.240.0.0 0.15.255.255 1,048,576 4,096
/13 255.248.0.0 0.7.255.255 524,288 2,048
/14 255.252.0.0 0.3.255.255 262,144 1,024
/15 255.254.0.0 0.1.255.255 131,072 512
/16 255.255.0.0 0.0.255.255 65,536 256
/17 255.255.128 0.0.127.255 32,768 128
/18 255.255.192 0.0.63.255 16,384 64
/19 255.255.224 0.0.31.255 8,192 32
/20 255.255.240 0.0.15.255 4,096 16
/21 255.255.248 0.0.7.255 2,048 8
/22 255.255.252 0.0.3.255 1,024 4
/23 255.255.254 0.0.1.255 512 2
/24 255.255.255.0 0.0.0.255 256 1
/25 255.255.255.128 0.0.0.127 128 1/2
/26 255.255.255.192 0.0.0.63 64 1/4
/27 255.255.255.224 0.0.0.31 32 1/8
/28 255.255.255.240 0.0.0.15 16 1/16
/29 255.255.255.248 0.0.0.7 8 1/32
/30 255.255.255.252 0.0.0.3 4 1/64
/31 255.255.255.254 0.0.0.1 2 1/128
/32 255.255.255.255 0.0.0.0 1 1/256

IPv6 Every 4th Subnet Mask Table

Bits Network Size
/0 xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/4 fxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/8 fcxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/12 fc0x:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/16 fc00:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/20 fc00:1xxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/24 fc00:12xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/28 fc00:123x:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/32 fc00:1234:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
/36 fc00:1234:1xxx:xxxx:xxxx:xxxx:xxxx:xxxx
/40 fc00:1234:12xx:xxxx:xxxx:xxxx:xxxx:xxxx
/44 fc00:1234:123x:xxxx:xxxx:xxxx:xxxx:xxxx
/48 fc00:1234:1234:xxxx:xxxx:xxxx:xxxx:xxxx
/52 fc00:1234:1234:1xxx:xxxx:xxxx:xxxx:xxxx
/56 fc00:1234:1234:12xx:xxxx:xxxx:xxxx:xxxx
/60 fc00:1234:1234:123x:xxxx:xxxx:xxxx:xxxx
/64 fc00:1234:1234:1234:xxxx:xxxx:xxxx:xxxx
/68 fc00:1234:1234:1234:1xxx:xxxx:xxxx:xxxx
/72 fc00:1234:1234:1234:12xx:xxxx:xxxx:xxxx
/76 fc00:1234:1234:1234:123x:xxxx:xxxx:xxxx
/80 fc00:1234:1234:1234:1234:xxxx:xxxx:xxxx
/84 fc00:1234:1234:1234:1234:1xxx:xxxx:xxxx
/88 fc00:1234:1234:1234:1234:12xx:xxxx:xxxx
/92 fc00:1234:1234:1234:1234:123x:xxxx:xxxx
/96 fc00:1234:1234:1234:1234:1234:xxxx:xxxx
/100 fc00:1234:1234:1234:1234:1234:1xxx:xxxx
/104 fc00:1234:1234:1234:1234:1234:12xx:xxxx
/108 fc00:1234:1234:1234:1234:1234:123x:xxxx
/112 fc00:1234:1234:1234:1234:1234:1234:xxxx
/116 fc00:1234:1234:1234:1234:1234:1234:1xxx
/120 fc00:1234:1234:1234:1234:1234:1234:12xx
/124 fc00:1234:1234:1234:1234:1234:1234:123x
/128 fc00:1234:1234:1234:1234:1234:1234:1234
 
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