DRAFT CHARTER ============= Multiparty Multimedia Session Control (mmusic) Last Modified: 2003-02-06 Chair(s): Joerg Ott Colin Perkins Transport Area Director(s): Scott Bradner Allison Mankin Transport Area Advisor: Allison Mankin Mailing Lists: General Discussion: mmusic@ietf.org To Subscribe: mmusic-request@ietf.org In Body: subscribe your_email_address Archive: http://www.ietf.org/mailman/listinfo/mmusic Description of Working Group: The Multiparty MUltimedia SessIon Control (MMUSIC) Working Group (WG) was chartered to develop protocols to support Internet teleconferencing and multimedia communications. These protocols are now reasonably mature, and many have received widespread deployment. The group is now focussed on the revisions of these protocols in the light of implementation experience and additional demands that have arisen from other WGs (such as AVT, SIP, SIPPING, and MEGACO). Multimedia communications protocols use a common platform for expressing media and session descriptions. This is the Session Description Protocol, SDP. The many uses of SDP have led to (requests for) numerous extensions and have led to recognition of several flaws in the protocol design. In spite of these, it is widely deployed. - To support this current deployment, MMUSIC will revise SDP suitable for publication as a Draft Standard RFC. This will involve correcting minor bugs and clarifying the current specification. - Various extensions to SDP will be pursued to remedy the most urgent of SDP's shortcomings. These will be limited to use of SDP in conjunction with connection-oriented media such as TCP and SCTP, offering support to work with NATs and firewalls, exchange of media session security keys. Apart from these, which are explicitly agreed to by the Area Directors and shown in the milestones, only extensions within the existing framework of SDP will be done (e.g. registering new codecs and defining parameters for them extending SDP to include new address families). To address the more fundamental issues with SDP, a next generation of SDP, referred to as SDPng, has been in progress and will be continued towards a Proposed Standard RFC. A requirements document will be devised that gathers the requirements from the areas in which SDP is currently deployed. MMUSIC will continue to maintain and revise the specification of the Real Time Streaming Protocol (RTSP) based on implementation experience. The RTSP specification will be revised to include various fixes and clarifications. Depending on the changes, the revised RTSP specification will be re-issued as either a Proposed or Draft Standard RFC. An MIB will be considered. MMUSIC will pursue work on Internet Media Guides (IMG), a generalization of our prior work on session announcements in two ways: 1) in addition to announcements (push) asynchronous notifications and retrieval shall be supported; and 2) the scope of session descriptions shall be expanded to cover general meta-data on Internet media. The purpose of is work is to enable users of Internet hosts to discover files, resources and multimedia programmes being multicast or unicast, available for streaming, or for download. The Internet Media Guide is applicable to a wide variety of Internet hosts and communication links. In order to achieve this the item is divided into four tasks: 1) Requirements and Framework of IMG; 2) Multicast/Unidirectional delivery of IMG; 3) Unicast/Bidirectional delivery of IMG; 4) IMG metadata base specification. The work in these tasks will build on, extend and leverage the prior work of MMUSIC and other working groups where applicable and avoid introduction of new protocols as far as possible. Regarding task 2), the work produced by the Reliable Multicast Transport (RMT) WG will be reused where feasible. Close cooperation with other bodies such as DVB is envisioned. Note that 4) will primarily tie together information from other groups and describe its use rather than developing new meta data specifications. The MMUSIC work items will be pursued in close coordination with other IETF WGs related to multimedia conferencing and IP telephony (AVT, SIP, SIPPING, IPTEL, MEGACO). Where appropriate, new separate working groups may be split off (as has happened with the SIP WG). The Working Group is also charged with addressing security issues related to the protocols it develops. Goals and Milestones: FEB 03 Submit revised SDP spec for Proposed (or Draft) Standard FEB 03 Submit SDP key management for Proposed Standard FEB 03 Submit SDP extensions for connection-oriented media for Proposed Standard FEB 03 Submit SDPng Transition document for Informational MAR 03 Submit SDP source filter extensions for Proposed Standard MAR 03 Submit draft on SDPng motivations, comparisons with current SDP capabilities. Request charter review on SDPng work from IAB and IESG. JUN 03 Submit SDPng base spec profile for Proposed Standard JUN 03 Submit IMG requirements and framework for Informational AUG 03 Submit IMG multicast/unidirectional delivery for Experimental AUG 03 Submit SDPng RTP profile spec for Proposed Standard AUG 03 Submit SDPng audio profile spec for Proposed Standard SEP 03 Submit SDPng video profile spec for Proposed Standard OCT 03 Submit revised RTSP spec for Proposed or Draft Standard (as appropriate) OCT 03 Submit SDP Offer/Answer examples for Informational OCT 03 Submit IMG unicast/bidirectional delivery spec for Proposed Standard DEC 03 Submit RTSP MIB for Proposed Standard JAN 04 Submit IMG meta-data spec for Experimental