RFC 6285: Unicast-Based Rapid Acquisition of Multicast RTP Sessions
In plain English — editorial summary, not part of the RFC
When an RTP receiver joins a multicast session, it may need to acquire and parse certain Reference Information before it can process any data sent in the multicast session. Depending on the join time, length of the Reference Information repetition (or appearance) interval, size of the Reference Information, and the application and transport properties, the time lag before an RTP receiver can usefully consume the multicast data, which we refer to as the Acquisition Delay, varies and can be large. This is an undesirable phenomenon for receivers that frequently switch among different multicast sessions, such as video broadcasts. In this document, we describe a method using the existing RTP and RTP Control Protocol (RTCP) machinery that reduces the acquisition delay. In this method, an auxiliary unicast RTP session carrying the Reference Information to the receiver precedes or accompanies the multicast stream. This unicast RTP flow can be transmitted at a faster than natural bitrate to further accelerate the acquisition. The motivating use case for this capability is multicast applications that carry real-time compressed audio and video. However, this method can also be used in other types of multicast applications where the acquisition delay is long enough to be a problem. [STANDARDS-TRACK]
Document record
- Document ID
- RFC6285
- Published
- June 2011
- Authors
- B. Ver Steeg; A. Begen; T. Van Caenegem; Z. Vax
- Status
- PROPOSED STANDARD
- Stream
- IETF
- Area
- rai
- Pages
- 56
- Also known as
- —
Topics
Related documents
Ranked automatically by shared keywords, IETF area and stream — not by editorial selection.
- RFC 6332Multicast Acquisition Report Block Type for RTP Control Protocol (RTCP) Extended Reports (XRs)Current
July 2011
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November 2015
- RFC 8114Delivery of IPv4 Multicast Services to IPv4 Clients over an IPv6 Multicast NetworkCurrent
March 2017
- RFC 8638IPv4 Multicast over an IPv6 Multicast in Softwire Mesh NetworksCurrent
September 2019
- RFC 8777DNS Reverse IP Automatic Multicast Tunneling (AMT) DiscoveryCurrent
April 2020
- RFC 8815Deprecating Any-Source Multicast (ASM) for Interdomain MulticastCurrent
August 2020
- RFC 9706TreeDN: Tree-Based Content Delivery Network (CDN) for Live Streaming to Mass AudiencesCurrent
January 2025
- RFC 6051Rapid Synchronisation of RTP FlowsCurrent
November 2010
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The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.
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