Indicating Exclusive Support of RTP and RTP Control Protocol (RTCP) Multiplexing Using the Session Description Protocol (SDP)
RFC 8858

Approval announcement
Draft of message to be sent after approval:

From: The IESG <>
To: "IETF-Announce" <>
Cc:,,,, "Flemming Andreasen" <>, "The IESG" <>,,
Subject: Protocol Action: 'Indicating Exclusive Support of RTP/RTCP Multiplexing using SDP' to Proposed Standard (draft-ietf-mmusic-mux-exclusive-10.txt)

The IESG has approved the following document:
- 'Indicating Exclusive Support of RTP/RTCP Multiplexing using SDP'
  (draft-ietf-mmusic-mux-exclusive-10.txt) as Proposed Standard

This document is the product of the Multiparty Multimedia Session Control
Working Group.

The IESG contact persons are Alexey Melnikov, Ben Campbell and Alissa

A URL of this Internet Draft is:

Technical Summary

   This document defines a new SDP media-level attribute, 'rtcp-mux-only', 
   that can be used by an endpoint to indicate exclusive support of RTP/RTCP 
   multiplexing.  The document also updates RFC 5761, by clarifying that an 
   offerer can use a mechanism to indicate that it is not able to send and 
   receive RTCP on separate ports.

Working Group Summary

   A WGLC was originally issued on the -03 version, which led to a 
   couple of WG participants questioning the need for the mechanism 
   After considerable discussion and discussion at IETF95, there was WG consensus
    to continue with the solution 
   The consensus was confirmed on the mailing list with several indications of support and no objections.  

Document Quality

   At least two major browser vendors have indicated that their intention is to 
   only support multiplexed RTP/RTCP for their WebRTC support.
   At least one WebRTC gateway vendor has indicated that they will support the 
   protocol, in order to recognize WebRTC entities that only support multiplexed 
  RTP/RTCP.  The protocol has been adopted by 3GPP, and is mandatory to 
  implement within the eP-CSCF function, which contains e.g. WebRTC gateway functionality.

   Reviewers that merit special mention are Roman Shpount, Paul Kyzivat and Martin Thomson.


   Flemming Andreasen is the Document Shepherd and 
   Ben Campbell is the Responsible AD.