Protocol Action: 'Support for Multiple Clock Rates in an RTP Session' to Proposed Standard (draft-ietf-avtext-multiple-clock-rates-11.txt)

The IESG <> Tue, 21 January 2014 14:21 UTC

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Subject: Protocol Action: 'Support for Multiple Clock Rates in an RTP Session' to Proposed Standard (draft-ietf-avtext-multiple-clock-rates-11.txt)
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The IESG has approved the following document:
- 'Support for Multiple Clock Rates in an RTP Session'
  (draft-ietf-avtext-multiple-clock-rates-11.txt) as Proposed Standard

This document is the product of the Audio/Video Transport Extensions
Working Group.

The IESG contact persons are Gonzalo Camarillo and Richard Barnes.

A URL of this Internet Draft is:

Technical Summary

This document clarifies the RTP specification when different clock rates are used in an RTP session.  It also provides guidance on how to interoperate with legacy RTP implementations that use multiple clock rates. It updates RFC 3550.

Working Group Summary

The document went through a working group last call.  There were comments and the document was updated to resolve all comments.

The work began in the context of the AVT working group, following a mailing list discussion in which several problems in RFC 3550 became clear.  The work became a work item of the AVTEXT working group following the split of AVT.

Document Quality

The document got good reviews from AVText members.  Several existing implementations implement the behavior recommended by the draft.   In order to ensure the correctness of the document's recommendations about interoperability with legacy implementations, a review of existing RTP stack behavior was performed at SIPit 26.


The Document Shepherd is Jonathan Lennox.  The Responsible Area Director is Gonzalo Camarillo.