Extended RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/AVPF)
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From: The IESG <firstname.lastname@example.org> To: IETF-Announce <email@example.com> Cc: Internet Architecture Board <firstname.lastname@example.org>, RFC Editor <email@example.com>, avt mailing list <firstname.lastname@example.org>, avt chair <email@example.com> Subject: Protocol Action: 'Extended RTP Profile for RTCP-based Feedback(RTP/AVPF)' to Proposed Standard The IESG has approved the following documents: - 'Extended RTP Profile for RTCP-based Feedback(RTP/AVPF) ' <draft-ietf-avt-rtcp-feedback-12.txt> as a Proposed Standard - 'Extended RTP Profile for RTCP-based Feedback - Results of the Timing Rule Simulations ' <draft-burmeister-avt-rtcp-feedback-sim-07.txt> as an Informational RFC These documents are products of the Audio/Video Transport Working Group. The IESG contact persons are Allison Mankin and Jon Peterson. A URL of this Internet-Draft is: http://www.ietf.org/internet-drafts/draft-ietf-avt-rtcp-feedback-12.txt
Technical Summary Real-time media streams that use RTP are, to some degree, resilient against packet losses. Receivers may use the base mechanisms of RTCP to report packet reception statistics and thus allow a sender to adapt its transmission behavior in the mid-term as sole means for feedback and feedback-based error repair (besides a few codec- specific mechanisms). This document defines an extension to the Audio-visual Profile (AVP) that enables receivers to provide, statistically, more immediate feedback to the senders and thus allow for short-term adaptation and efficient feedback-based repair mechanisms to be implemented. This early feedback profile (AVPF) maintains the AVP bandwidth constraints for RTCP and preserves scalability to large groups. This profile establishes specific repair uses for applications, and a few general uses based on NACK. It is not intended to enable RTCP to provide congestion control feedback. Working Group Summary The working group supported this document. Protocol Quality The accompanying Informational document supports the claims that statistically the RTCP scaling of this feedback is compatible with that of RFC 3550. There are also prototype implementations. Working group review of the document especially covered the scalability and security compatibility issues. Allison Mankin reviewed the documents for the IESG.