IPv6 Adresses

Defined in RFC 5156

  • ::1/128 is the loopback address
  • ::/128 is the unspecified address
  • ::FFFF:0:0/96 are the IPv4-mapped addresses (indicating devices that are not IPv6-capable)
  • ::<ipv4-address>/96 are the IPv4-compatible addresses, deprecated!
  • fe80::/10 are the link-local unicast addresses
  • fc00::/7 are the unique-local addresses
  • 2001:db8::/32 are the documentation addresses. They are used for documentation purposes such as user manuals, RFCs, etc.
  • 2002::/16 are the 6to4 addresses
  • 2001::/32 are the Teredo addresses
  • ::/0 is the default unicast route address
  • ff00::/8 are multicast addresses

See "Special-Use IPv6 Addresses" (RFC 5156): http://tools.ietf.org/html/rfc5156

Private addresses

Private addresses are indicated by the address having 1111 1110 1 for the first nine bits. Thus, private addresses have a first octet value of 0xFE in hexadecimal, with the next hex digit being from 8 to F. These addresses are further divided into two types based on their scope. IPv6 site-local addresses allow data to be sent only to the devices within a site or organization. They begin with FEC, FED, FEE or FEF in hexadecimal and they are the equivalent of private addresses of IPv4.
IPv6 link-local addresses are used only on a particular local link (physical network), typically for special purposes such as address resolution or neighbor discovery. They start with FE8, FE9, FEA or FEB.

For further information see "IPv6 Special Addresses: Reserved, Private (Link-Local / Site-Local), Unspecified and Loopback" at http://www.tcpipguide.com/free/t_IPv6SpecialAddressesReservedPrivateLinkLocalSiteLo.htm


Multicast addresses in IPv6 have the prefix ff00::/8.

The four least-significant bits of the second address octet of a multicast address ( the X in ff0X::) identify the address scope, i.e. the span over which the multicast address is propagated. Currently defined scopes are: interface-local (1), link-local (2), admin-local (4), site-local (5), organization-local (8), and global (e). Values 0 and f are reserved.