All types of multimedia communications are based upon a common platform for expressing media streams (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 for key applications of SDP. MMUSIC will revise the SDP specification suitable for publication as a draft standard to address minor revision and further support the current broad deployment. Work on an SDP MIB will be considered.
Various extensions to SDP will be pursued to remedy the most urgent of SDP's shortcomings: However, these are limited to, adding means for identifying and semantically grouping media sessions, providing limited expressiveness for simultaneous capabilities, use of SDP in conjunction with connection-oriented media such as TCP and SCTP, offering support to work with NATs and firewalls, and documenting the use of SDP in SIP as a separate document. Existing key exchange per media session in SDP will be cleaned up in a revision of that portion of RFCxxxx. 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 -- such as 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 standards track document. A requirements document will be devised that gathers the individual requirements from the areas in which SDP is currently deployed. Work on an SDPng MIB will be considered.
MMUSIC will continue to maintain and revise the specification of the Real Time Streaming Protocol (RTSP) based on implementation experience. The RTSP spec will be revised to include various fixes and clarifications. Depending on the changes, the revised RTSP spec will be re-issued as Proposed or go to Draft Standard. A MIB will also be defined.
The WG's 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 will 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.
| Done | Submit SDP to the IESG for consideration as a Proposed Standard. | |
| Done | Conduct WG Last Call for SAP Internet-Draft | |
| Done | Submit a revised SIP I-D. | |
| Done | Submit a revised Internet Multimedia Conferencing Architecture I-D. | |
| Done | Submit SAP Internet-Draft to IESG for publication as an Experimental Protocol. | |
| Done | Conduct WG Last Call for RTSP Internet-Draft. | |
| Done | Submit Internet-Draft on Internet Multimedia Conferencing Architecture. | |
| Done | Submit RTSP to IESG for consideration as a Proposed Standard. | |
| Done | Conduct WG Last Call for SIP Internet-Draft. | |
| Done | Submit SIP Internet-Draft to IESG for consideration as a Proposed Standard. | |
| Done | Conduct WG Last Call for SAP Security Internet-Draft. | |
| Done | Conduct second WG Last Call for SAP. | |
| Done | Submit SAP Internet-Draft to IESG for consideration as a Proposed Standard. | |
| Done | Submit SAP Security Internet-Draft to IESG for consideration as a Proposed Standard. | |
| Done | Submit IPv6 Extensions to SDP for Proposed Standard | |
| Done | Submit SIP's offer/answer use of SDP for Proposed Standard | |
| Done | Submit SDP4NAT for Proposed Standard (Informational?) | |
| Feb 02 | Submit revised SDP spec for Proposed (or Draft) Standard | |
| Feb 02 | Submit draft on SDPng motivations, comparisons with current SDP capabilities. Request charter review on SDPng work from IAB and IESG. | |
| Mar 02 | Submit SDP key management for Proposed Standard | |
| Apr 02 | `Submit SDPng base spec and audio profile for Proposed Standard | |
| May 02 | Submit revised RTSP spec for Proposed or Draft Standard (as appropriate) | |
| Jun 02 | Submit SDPng video profile spec for Proposed Standard | |
| Jul 02 | Submit RTSP MIB for Proposed Standard | |
| Jul 02 | Conclude WG |
| RFC | Status | Title |
| RFC2326 | PS | Real Time Streaming Protocol (RTSP) |
| RFC2327 | PS | SDP: Session Description Protocol |
| RFC2543 | PS | SIP: Session Initiation Protocol |
| RFC2974 | E | Session Announcement Protocol |
| RFC3108 | PS | Conventions for the use of the Session Description Protocol (SDP)for ATM Bearer Connections |