--- avt-charter-00.txt 2006-08-11 15:57:55.000000000 -0700 +++ avt-charter-01.txt 2006-08-11 16:42:00.000000000 -0700 @@ -1,75 +1,100 @@ +Description of Working Group: -The Audio/Video Transport Working Group was formed to specify a -protocol for real-time transmission of audio and video over unicast -and multicast UDP/IP. This is the Real-time Transport Protocol, RTP, -together with its associated profiles and payload formats. The -current aims of the working group are: - -- to review and revise existing payload formats to advance those - which are useful to Draft Standard, and to declare others - as Historic. Milestones will be established as a champion for - each payload format is identified. - -- to develop payload formats for new media codecs, and to - document best-current practices in payload format design. - The group continues to be precluded from work on codecs - themselves because of overlap with the other standards - bodies, and because the IETF does not have the ability - to effectively review new codecs. An exception was made - for the freeware iLBC codec on a highly experimental basis, - but acceptance of new codec work is unexpected and subject +The Audio/Video Transport Working Group was formed to specify a protocol for +real-time transmission of audio and video over unicast and multicast +UDP/IP. This is the Real-time Transport Protocol, RTP, together with its +associated profiles and payload formats. The current aims of the working group +are: + +- to review and revise existing payload formats to advance those which are + useful to Draft Standard, and to declare others as Historic. Milestones will + be established as a champion for each payload format is identified. + +- to develop payload formats for new media codecs, and to document best-current + practices in payload format design. The group continues to be precluded from + work on codecs themselves because of overlap with the other standards bodies, + and because the IETF does not have the ability to effectively review new + codecs. An exception was made for the freeware iLBC codec on a highly + experimental basis, but acceptance of new codec work is unexpected and subject to rechartering. -- to complete the forward error correction work to update - RFC 2733 in the form of the ULP payload format +- to complete the forward error correction work to update RFC 2733 in the form + of the ULP payload format -- to investigate and if suitable develop a framework for advanced - FEC codes and their usage for RTP, possibly with alignment to - the RMT WG's FEC building block. - -- to extend RTP to work with Source-Specific Multicast sessions - with unicast feedback +- to extend RTP to work with Source-Specific Multicast sessions with unicast + feedback - to provide a framing mechanism for RTP over TCP and TLS -- in collaboration with the MPLS and ROHC WGs, to develop a solution - for header compression of RTP across MPLS networks that avoid - decompression and compression at each MPLS node. - -- to develop a new RTP profile as the combination of the SRTP - profile and the Extended RTP Profile for RTCP-based Feedback - (RTP/SAVPF) - -- to develop a new RTP profile for usage of TFRC (RFC 3448) with - RTP over UDP to allow application developers to gain experience - with TCP friendly congestion control. +- in collaboration with the MPLS and ROHC WGs, to develop a solution for header + compression of RTP across MPLS networks that avoid decompression and + compression at each MPLS node. + +- to develop a RTP profile for the combination of the SRTP profile and the + Extended RTP Profile for RTCP-based Feedback (RTP/SAVPF) + +- to maintain and enhance the SRTP Profile, with review and input from the + Security Area + +- to develop a new RTP profile for usage of TFRC (RFC 3448) with RTP over UDP to + allow application developers to gain experience with TCP friendly congestion + control. - to develop a MIB for RTCP XR (RFC 3611). - to update the RTP MIB, including aligning it with RFC 3550. -The longer term goals of the working group are to advance the -SRTP Profile, the Extended RTP Profile for RTCP-based Feedback, -the Compressed RTP framework, and the RTP MIB to Draft Standard. - -The group has no plans to develop new RTP profiles beyond those -listed above, but will consider rechartering to produce profile -level extensions if appropriate. +- to clarify how RTP is used for media in conferencing with centralized nodes + performing relay, translation or mixing of media. + +- to develop the mechanisms needed for efficient control of media and its + encoding process in RTP based conferencing, both over multicast and transport + containing relays, translators and mixers. An example of such a mechanism is + the full intra request. Used to allow joining participants to receive video + with good quality from the start. It also allows mixers to perform switching + between media sources without the need to encode the media once more. + +- to develop a solution for carrying media meta data, specifically SMPTE + timestamps, to enhance the media stream. Such transport may be done in either + RTP or RTCP depending on which is most suitable. The WG may consider if a + generalized mechanism should be developed to enable future types of meta data + to be easier to include. + +- to develop two new metric blocks for the RTCP XR (RFC 3611) framework to + provide information on the media quality experienced by the receiver of RTP + flows. One metrics block is for high resolution measurements of audio and + speech quality. A second one for providing information on the quality of + video. The timescale to complete this second block and the included metrics + are highly dependable on the development of standardized subjective metrics + for video quality. The WG will consider what metrics that are available and if + they should be included or not. The metrics blocks shall not duplicate + signaling information anyway necessary for the establishment of the session. + +The longer term goals of the working group are to advance the SRTP Profile, the +Extended RTP Profile for RTCP-based Feedback, the Compressed RTP framework, and +the RTP MIB to Draft Standard. + +The group has no plans to develop new RTP profiles beyond those listed above, +but will consider rechartering to produce profile level extensions if +appropriate. + Goals and Milestones: -Done Review DCCP including prototypes and API; feedback to DCCP WG -Done Initial draft requirements for ECRTP over MPLS; discuss with MPLS WG -Done Submit iLBC payload format for Proposed Standard -Done Submit iLBC codec specification for Experimental -Done Advance RTP specification and A/V profile to Full Standard Done Submit RTP/SAVPF profile for Proposed Standard Nov 2005 Submit ULP Payload Format for Proposed Standard Done Finished investigation of advanced FEC codes for RTP, update plan -Dec 2005 Submit any extensions for RTP HC on MPLS networks for Proposed Standard -Mar 2006 Submit RTCP/SSM draft for Proposed Standard +Dec 2005 Submit extensions for RTP HC on MPLS networks for Proposed Standard Mar 2006 Submit SRTP for Draft Standard -Mar 2006 Submit RTP Profile for TFRC for Proposed Standard -Aug 2006 Submit update of RTP MIB for Proposed or Draft Standard -Aug 2006 Submit RTCP XR MIB for Proposed Standard -Sep 2006 Submit RTP/AVPF for Draft Standard +Aug 2006 Submit SMTPE Timestamping of Media for Proposed Standard +Sep 2006 Submit RTCP/SSM draft for Proposed Standard +Nov 2006 Submit "use of AES-192 and AES-256 in SRTP" for Proposed standard +Nov 2006 Submit update of RTP MIB for Proposed or Draft Standard +Nov 2006 Submit RTCP XR MIB for Proposed Standard +Nov 2006 Submit RTP Profile for TFRC for Proposed Standard +Nov 2006 Submit RTCP XR High Resolution Audio Metrics for Proposed Standard +Nov 2006 Submit Codec Control Messages for Proposed Standard +Mar 2007 Submit SRTP for Draft Standard +Mar 2007 Submit RTCP XR Video Metrics block for Proposed Standard +Sep 2007 Submit RTP/AVPF for Draft Standard +