IPv6 Address Space

Last Updated

2025-10-23

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.

As stated in [RFC3513], IANA should limit its allocation of 
IPv6-unicast address space to the range of addresses that start with
binary value 001. The rest of the global unicast address space 
(approximately 85% of the IPv6 address space) is reserved for future
definition and use, and is not to be assigned by IANA at this time.
        
While [RFC3513] was obsoleted by [RFC4291], the guidance provided to
IANA did not change regarding the allocation of IPv6 unicast 
addresses.
        
  

Formerly known as

Internet Protocol Version 6 Address Space (pursuant to [IESG decision])

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Registration Procedure(s)

IETF Review

Reference

[RFC9812]

Available Formats

CSV