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 Cooper. A URL of this Internet Draft is: https://datatracker.ietf.org/doc/draft-ietf-mmusic-mux-exclusive/ 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 (https://mailarchive.ietf.org/arch/msg/mmusic/7fcpfQWcfV8qkWFyAaaVl_2xBGA). After considerable discussion and discussion at IETF95, there was WG consensus to continue with the solution (https://mailarchive.ietf.org/arch/msg/mmusic/5OWNyDa4PpLbeX5mZ77zYMjqsBA). 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. Personnel Flemming Andreasen is the Document Shepherd and Ben Campbell is the Responsible AD.