Internet Protocol Version 6 Address Space

   Last Updated
           2010-10-29

   Note

 The IPv6 address management function was formally delegated to
     IANA in December 1995 [RFC1881]. The registration procedure
     was confirmed with the IETF Chair in march 2010.

   This registry is also available in plain text.

   Registration Procedures

 IESG Approval

   IPv6 Prefix      Allocation      Reference   Note
   0000::/8    Reserved by IETF     [RFC4291] [1][5][6]
   0100::/8    Reserved by IETF     [RFC4291]
   0200::/7    Reserved by IETF     [RFC4048] [2]
   0400::/6    Reserved by IETF     [RFC4291]
   0800::/5    Reserved by IETF     [RFC4291]
   1000::/4    Reserved by IETF     [RFC4291]
   2000::/3    Global Unicast       [RFC4291] [3]
   4000::/3    Reserved by IETF     [RFC4291]
   6000::/3    Reserved by IETF     [RFC4291]
   8000::/3    Reserved by IETF     [RFC4291]
   A000::/3    Reserved by IETF     [RFC4291]
   C000::/3    Reserved by IETF     [RFC4291]
   E000::/4    Reserved by IETF     [RFC4291]
   F000::/5    Reserved by IETF     [RFC4291]
   F800::/6    Reserved by IETF     [RFC4291]
   FC00::/7    Unique Local Unicast [RFC4193]
   FE00::/9    Reserved by IETF     [RFC4291]
   FE80::/10   Link Local Unicast   [RFC4291]
   FEC0::/10   Reserved by IETF     [RFC3879] [4]
   FF00::/8    Multicast            [RFC4291]

                                                                      Footnotes

   [1] The "unspecified address", the "loopback address", and the IPv6
       Addresses with Embedded IPv4 Addresses are assigned out of the
       0000::/8 address block.
   [2] 0200::/7 was previously defined as an OSI NSAP-mapped prefix set
       [RFC4548]. This definition has been deprecated as of December
       2004 [RFC4048].
   [3] The IPv6 Unicast space encompasses the entire IPv6 address range
       with the exception of FF00::/8. [RFC4291] IANA unicast address
       assignments are currently limited to the IPv6 unicast address
       range of 2000::/3. IANA assignments from this block are registered
       in the IANA registry: [IANA registry ipv6-unicast-address-assignments].
   [4] FEC0::/10 was previously defined as a Site-Local scoped address
       prefix. This definition has been deprecated as of September 2004
       [RFC3879].
   [5] 0000::/96 was previously defined as the "IPv4-compatible IPv6
       address" prefix.  This definition has been deprecated by [RFC4291].
   [6] The "Well Known Prefix" 64:ff9b::/96 used in an algorithmic
       mapping between IPv4 to IPv6 addresses is defined out of the
       0000::/8 address block, per [RFC6052].