The IESG has approved the following document: - 'Discovery of the IPv6 Prefix Used for IPv6 Address Synthesis' (draft-ietf-behave-nat64-discovery-heuristic-17.txt) as Proposed Standard This document is the product of the Behavior Engineering for Hindrance Avoidance Working Group. The IESG contact persons are Martin Stiemerling and Spencer Dawkins. A URL of this Internet Draft is: http://datatracker.ietf.org/doc/draft-ietf-behave-nat64-discovery-heuristic/ Technical Summary This document describes a method for detecting the presence of DNS64 and for learning the IPv6 prefix used for protocol translation on an access network. The method depends on the existence of a well-known IPv4-only domain name "ipv4only.arpa". The information learned enables nodes to perform local IPv6 address synthesis and to potentially avoid NAT64 on dual-stack and multi-interface deployments. Working Group Summary The document specifies a heuristic that is not perfect and so some points were rough, but the constraint for this document was to operate without changes to code (only configuration) in existing networks. Given that constraint, there was strong consensus. Relaxing the constraint would allow one to do better, and that is the focus of a draft recently submitted to the PCP WG. Document Quality Jouni Korhonen did a prototype implementation that was presented in the WG but not included in commercial product. Additionally, Cameron Byrne (T-Mobile USA) has a 464XLAT implementation that also implements this draft, as noted at https://sites.google.com/site/tmoipv6/464xlat#TOC-Android-CLAT-on-a-UMTS-IPv6-only-network-with-DNS64-NAT64 Personnel Document Shepherd: Dave Thaler (dthaler@microsoft.com) Responsible Area Director: Martin Stiemerling
