A modified charter has been submitted for Multiparty Multimedia Session Control (mmusic) in the Transport Area of the IETF. The IESG has not made any determination as yet. The following description was submitted, and is provided for informational purposes only. Multiparty Multimedia Session Control (mmusic) ------------------------------------- Current Status: Active Working Group 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. A MIB will be considered. An Internet Media Guide (IMG) is a collection of multimedia session descriptions expressed using SDP, SDPng or some similar session description format. It is used to describe a collection of multimedia sessions (e.g. television programme schedules). The IMG must be delivered to a potentially large audience, who use it to join a subset of the sessions described, and who may need to be notified of changes to the IMG. MMUSIC will investigate work on delivery mechanisms for IMGs, generalizing its work on session announcement and discovery protocols (SAP, RTSP, SIP). We will investigate and document requirements for IMG delivery mechanisms, and identify the requirements that these delivery mechanisms impose on the session description formats used by the IMG. We will then work to produce a framework document outlining the use of (existing) protocols to create an IMG delivery infrastructure. After successful completion of these initial milestones for IMG delivery, the MMUSIC working group will decide whether or not MMUSIC is the proper place to pursue any needed mechanisms for IMGs, and if so, recharter accordingly 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: APR 03 Submit SDP source filter extensions for Proposed Standard MAY 03 Submit draft on SDPng motivations, comparisons with current SDP capabilities. Request charter review on SDPng work from IAB and IESG. JUL 03 Submit revised SDP spec for Proposed Standard JUL 03 Submit IMG requirements and framework for Informational JUL 03 Review work on IMGs and update charter accordingly AUG 03 Submit SDPng base spec profile 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 NOV 03 Submit SDP security extension for Proposed Standard NOV 03 Submit SDPng RTP profile spec for Proposed Standard NOV 03 Submit SDPng audio profile spec for Proposed Standard NOV 03 Submit SDPng video profile spec for Proposed Standard DEC 03 Submit RTSP MIB for Proposed Standard