Subject: Protocol Action: 'Addressing Record-Route issues in the Session Initiation Protocol (SIP)' to Proposed Standard

From: The IESG <[email-masked]>
Date: Tue, 18 Aug 2009 10:47:53 -0700 (PDT)

The IESG has approved the following document:

- 'Addressing Record-Route issues in the Session Initiation Protocol 
   (SIP) '
   <draft-ietf-sip-record-route-fix-10.txt> as a Proposed Standard

This document is the product of the Session Initiation Protocol Working Group. 

The IESG contact persons are Robert Sparks and Cullen Jennings.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-sip-record-route-fix-10.txt

Technical Summary

  Multi-homed SIP proxies (having two or more interfaces)
  raise special requirements when handling SIP requests that
  have different ingress and egress interfaces.  One
  technique that has been widely deployed is to insert a
  single Record-Route header describing the egress interface.
  When another request in the  same dialog then traverses the
  proxy in a reverse direction, the proxy must edit the
  headers to reflect the new egress interface. This document
  formalizes another technique that has also been widely
  deployed and found to be simpler and more effective.  Using
  this technique, the proxy inserts two record-route headers,
  one for the ingress interface and one for the egress
  interface. This keeps the route symmetric, such that it can
  be traversed in the reverse direction without requiring
  examination and editing by the proxy, thereby reducing
  system complexity and processing load in the proxy.

Working Group Summary

  There is very strong consensus around the recommendations
  in this document. The working group spent significant time
  debating whether to produce these recommendations as a set
  of corrections to RFC3261 or as a BCP with the latter result.

Document Quality

   The practices documented here are significantly deployed
   and have been tested at many interoperability test events.   

Personnel

   Nils Ohlmeier is the Document Shepherd.
   Robert Sparks is the responsible Area Director.