RFC 6051: Rapid Synchronisation of RTP Flows
In plain English — editorial summary, not part of the RFC
This memo outlines how RTP sessions are synchronised, and discusses how rapidly such synchronisation can occur. We show that most RTP sessions can be synchronised immediately, but that the use of video switching multipoint conference units (MCUs) or large source-specific multicast (SSM) groups can greatly increase the synchronisation delay. This increase in delay can be unacceptable to some applications that use layered and/or multi-description codecs. This memo introduces three mechanisms to reduce the synchronisation delay for such sessions. First, it updates the RTP Control Protocol (RTCP) timing rules to reduce the initial synchronisation delay for SSM sessions. Second, a new feedback packet is defined for use with the extended RTP profile for RTCP-based feedback (RTP/AVPF), allowing video switching MCUs to rapidly request resynchronisation. Finally, new RTP header extensions are defined to allow rapid synchronisation of late joiners, and guarantee correct timestamp-based decoding order recovery for layered codecs in the presence of clock skew. [STANDARDS-TRACK]
Document record
- Document ID
- RFC6051
- Published
- November 2010
- Authors
- C. Perkins; T. Schierl
- Status
- PROPOSED STANDARD
- Stream
- IETF
- Area
- rai
- Pages
- 22
- Also known as
- —
- Updates:
- RFC 3550
Topics
Related documents
Ranked automatically by shared keywords, IETF area and stream — not by editorial selection.
- RFC 3556Session Description Protocol (SDP) Bandwidth Modifiers for RTP Control Protocol (RTCP) BandwidthCurrent
July 2003
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June 2014
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October 2006
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July 2006
- RFC 7728RTP Stream Pause and ResumeCurrent
February 2016
- RFC 8114Delivery of IPv4 Multicast Services to IPv4 Clients over an IPv6 Multicast NetworkCurrent
March 2017
- RFC 8115DHCPv6 Option for IPv4-Embedded Multicast and Unicast IPv6 PrefixesCurrent
March 2017
- RFC 3913Border Gateway Multicast Protocol (BGMP): Protocol SpecificationCurrent
September 2004
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