IPv6 Prefix Length Recommendation for Forwarding

Document Type Replaced Internet-Draft (individual)
Authors Mohamed Boucadair  , Alexandre Petrescu 
Last updated 2015-01-20 (latest revision 2014-09-24)
Replaced by RFC 7608, RFC 7608
Stream (None)
Expired & archived
pdf htmlized bibtex
Additional Resources
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Replaced by draft-ietf-v6ops-cidr-prefix, draft-ietf-v6ops-cidr-prefix
Telechat date
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


The length of IP prefixes is an information used by forwarding and routing processes is policy-based. As such, no maximum length must be assumed by design. Discussions on the 64-bit boundary in IPv6 addressing revealed a need for a clear recommendation on which bits must be used by forwarding decision-making processes. This document sketches a recommendation to be followed by forwarding and routing designs with regards to the prefix length. The aim is to avoid hard-coded routing and forwarding designs that exclude some IP prefix lengths.


Mohamed Boucadair (mohamed.boucadair@orange.com)
Alexandre Petrescu (alexandru.petrescu@cea.fr)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)