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-
- Audio/Video Transport (avt)
- ---------------------------
-
- Charter
-
- Chair(s):
- Stephen Casner <casner@isi.edu>
-
- Transport Area Director(s)
- Allison Mankin <mankin@cmf.nrl.navy.mil>
-
- Mailing lists:
- General Discussion:rem-conf@es.net
- To Subscribe: rem-conf-request@es.net
- Archive: nic.es.net:~/ietf/rem-conf/av-transport-archive
-
- 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 AV transport
- 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 Define the scope of the Working Group, and who might contribute. Our
- first step will be to solicit contributions of potential protocols
- from projects that have already developed packet audio and video.
- From these contributions we will distill the appropriate protocol
- features.
-
- 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 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.
-
- May 93 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>
- ------ ------- ------------------------------------------
- Oct 92 New <draft-ietf-avt-issues-00.txt, .ps>
- Issues in Designing a Transport Protocol for Audio and Video
- Conferences and other Multiparticipant Real-Time Applications
-
- Dec 92 May 93 <draft-ietf-avt-rtp-01.txt>
- A Transport Protocol for Real-Time Applications
-
- Dec 92 New <draft-ietf-avt-encodings-00.txt>
- Media Encodings
-
- Dec 92 New <draft-ietf-avt-profile-00.txt>
- Sample Profile for the Use of RTP for Audio and Video
- Conferences with Minimal Control
-
- Mar 93 New <draft-ietf-avt-video-packet-00.txt>
- Packetization of H.261 video streams
-
- Request For Comments:
-
- None to date.
-