RTP Payload Format for Bundled MPEG (RFC2343)
Original Publication Date: 1998-May-01
Included in the Prior Art Database: 2000-Sep-13
Internet Society Requests For Comment (RFCs)
M. Civanlar: AUTHOR [+3]
This document describes a payload type for bundled, MPEG-2 encoded video and audio data that may be used with RTP, version 2. Bundling has some advantages for this payload type particularly when it is used for video-on-demand applications. This payload type may be used when its advantages are important enough to sacrifice the modularity of having separate audio and video streams.
Network Working Group M. Civanlar
Request for Comments: 2343 G. Cash
Category: Experimental B. Haskell
RTP Payload Format for Bundled MPEG
Status of this Memo
This memo defines an Experimental Protocol for the Internet
community. This memo does not specify an Internet standard of any
kind. Discussion and suggestions for improvement are requested.
Distribution of this memo is unlimited.
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document describes a payload type for bundled, MPEG-2 encoded
video and audio data that may be used with RTP, version 2. Bundling
has some advantages for this payload type particularly when it is
used for video-on-demand applications. This payload type may be used
when its advantages are important enough to sacrifice the modularity
of having separate audio and video streams.
This document describes a bundled packetization scheme for MPEG-2
encoded audio and video streams using the Real-time Transport
Protocol (RTP), version 2 .
The MPEG-2 International standard consists of three layers: audio,
video and systems . The audio and the video layers define the
syntax and semantics of the corresponding "elementary streams." The
systems layer supports synchronization and interleaving of multiple
compressed streams, buffer initialization and management, and time
identification. RFC 2250  describes packetization techniques to
transport individual audio and video elementary streams as well as
the transport stream, which is defined at the system layer, using the
The bundled packetization scheme is needed because it has several
advantages over other schemes for some important applications
including video-on-demand (VOD) where, audio and video are always
used together. Its advantages over independent packetization of
audio and video are:
1. Uses a single port per "program" (i.e. bundled A/V). This may
increase the number of streams that can be served e.g., from a VOD
server. Also, it eliminates the performance hit when two ports are
used for the separate audio and video streams on the client side.
2. Provides implicit synchronization of audio and video. This is
particularly convenient when the A/V data is stored in an
interleaved format at the server.
3. Reduces the header overhead. Since using large packets increases
the effects of losses and delay, audio only packets need to be
smaller increasing the overhead. An A/V bundled format can provide
about 1% overall overhead reduction. Considering the high bitrates
used for MPEG-2 encoded material, e.g. 4 Mbps, the number of ...