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-
- Audio/Video Transport (avt)
- ---------------------------
-
- Charter
- Last Modified: 24-Oct-97
-
- Current Status: Active Working Group
-
- Chair(s):
- Stephen Casner <casner@precept.com>
-
- Transport Area Director(s):
- Scott Bradner <sob@harvard.edu>
- Allyn Romanow <allyn.romanow@eng.sun.com>
-
- Transport Area Advisor:
- Allyn Romanow <allyn.romanow@eng.sun.com>
-
- Mailing Lists:
- General Discussion:rem-conf@es.net
- To Subscribe: rem-conf-request@es.net
- Archive: ftp://nic.es.net/pub/mailing-lists/mail-archive/rem-conf
-
- Description of Working Group:
-
- The Audio/Video Transport Working Group was formed to specify
- experimental
- protocols for real-time transmission of audio and video over UDP
- and IP multicast. The focus of this group is near-term and its
- purpose is to integrate and coordinate the current AVT
- efforts of existing research activities. No standards-track
- protocols are expected to be produced because UDP transmission of
- audio and video is only sufficient for small-scale experiments
- over fast portions of the Internet. However, the transport
- protocols produced by this working group should be useful on a
- larger scale
- in the future in conjunction with additional protocols to access
- network-level resource management mechanisms. Those mechanisms,
- research efforts now, will provide low-delay service and guard
- against unfair consumption of bandwidth by audio/video traffic.
-
- Similarly, initial experiments can work without any connection
- establishment procedure so long as a priori agreements on port
- numbers and coding types have been made. To go beyond that, we
- will need to address simple control protocols as well. Since IP
- multicast traffic may be received by anyone, the control
- protocols must handle authentication and key exchange so that the
- audio/video data can be encrypted. More sophisticated connection
- management is also the subject of current research. It is
- expected that standards-track protocols integrating transport,
- resource management, and connection management will be the result
- of later working group efforts.
-
- The AVT Working Group may design independent protocols specific to
- each
- medium, or a common, lightweight, real-time transport protocol
- may be extracted. Sequencing of packets and synchronization
- among streams are important functions, so one issue is the form
- of timestamps and/or sequence numbers to be used. The working
- group will
- not focus on compression or coding algorithms which are domain of
- higher layers.
-
- Goals and Milestones:
-
- Done Conduct a teleconference working group meeting using a
- combination of packet audio and telephone. The topic will be a
- discussion of issues to be resolved in the process of
- synthesizing a new protocol.
-
- Done Define the scope of the working group, and who might
- contribute. The first step will be to solicit contributions of
- potential protocols from projects that have already developed
- packet audio and video. From these contributions the group
- will distill the appropriate protocol features.
-
- Done Review contributions of existing protocols, and discuss which
- features should be included and tradeoffs of different methods.
- Make writing assignments for first-draft documents.
-
- Done Post an Internet-Draft of the lightweight audio/video transport
- protocol.
-
- Done Post a revision of the AVT protocol addressing new work and
- security options as an Internet-Draft.
-
- Jun 93 Submit the AVT protocol to the IESG for consideration as an
- Experimental Protocol.
-
-
- Internet-Drafts:
-
- Posted Revised I-D Title <Filename>
- ------ ------- ------------------------------------------
- Mar 96 Jun 97 <draft-speer-avt-layered-video-02.txt>
- RTP usage with Layered Multimedia Streams
-
- Apr 96 Sep 97 <draft-ietf-avt-rtp-payload-04.txt>
- RTP Payload Format for H.263 Video Streams
-
- Aug 96 Feb 97 <draft-civanlar-bmpeg-01.txt>
- RTP Payload Format for Bundled MPEG
-
- Nov 96 Jul 97 <draft-ietf-avt-crtp-03.txt>
- Compressing IP/UDP/RTP Headers for Low-Speed Serial Links
-
- Nov 96 Jan 97 <draft-aboba-rtpscale-02.txt>
- Alternatives for Enhancing RTCP Scalability
-
- Mar 97 New <draft-ietf-avt-rtp-mib-00.txt>
- Real-Time Transport Protocol Management Information Base
-
- Mar 97 Jul 97 <draft-ietf-avt-profile-new-01.txt,.ps>
- RTP Profile for Audio and Video Conferences with Minimal
- Control
-
- Apr 97 Jun 97 <draft-ietf-avt-mpeg-new-01.txt>
- RTP Payload Format for MPEG1/MPEG2 Video
-
- Jul 97 New <draft-ietf-avt-qt-rtp-00.txt>
- RTP Payload Format for QuickTime Media Streams
-
- Jul 97 New <draft-ietf-avt-dtmf-00.txt,.ps>
- RTP Payload for DTMF Digits
-
- Aug 97 New <draft-ietf-avt-fec-00.txt>
- An A/V Profile Extension for Generic Forward Error Correction
- in RTP
-
- Aug 97 New <draft-ietf-avt-info-repair-00.txt>
- Options for Repair of Streaming Media
-
- Request For Comments:
-
- RFC Stat Published Title
- ------- -- ---------- -----------------------------------------
- RFC1889 PS Jan 96 RTP: A Transport Protocol for Real-Time Applications
-
- RFC1890 PS Jan 96 RTP Profile for Audio and Video Conferences with
- Minimal Control
-
- RFC2035 PS Oct 96 RTP Payload Format for JPEG-compressed Video
-
- RFC2032 PS Oct 96 RTP payload format for H.261 video streams
-
- RFC2038 PS Oct 96 RTP Payload Format for MPEG1/MPEG2 Video
-
- RFC2029 PS Oct 96 RTP Payload Format of Sun's CellB Video Encoding
-
- RFC2190 PS Sep 97 RTP Payload Format for H.263 Video Streams
-
- RFC2198 PS Sep 97 RTP Payload for Redundant Audio Data
-