IETF-95 Proceedings

Introduction  |  Area, Working Goup & BoF Reports  |  Plenaries  |  Training  |  Internet Research Task Force

Multiparty Multimedia Session Control (mmusic) (WG)

Minutes   |   Jabber Logs  |   Mailing List Archives

Additional information is available at


Applications and Real-Time Area Area Director(s):

Assigned Area Director


Meeting Slides:

Blue Sheets:


Request for Comments:

Charter (as of 2016-02-05):

The Multiparty MUltimedia SessIon Control (MMUSIC) Working Group was
originally chartered to develop protocols to support Internet
teleconferencing and multimedia communications. These protocols are now
reasonably mature, and many have received widespread deployment.
Currently, the group is focused on using and negotiating media streams
with the Session Description Protocol (SDP), which is used as a common
protocol to express media and session descriptions. The group also
maintains the Real-time Streaming Protocol (RTSP) specifications.

The group has revised these protocols in the light of implementation
experience and additional demands that have arisen from other WGs (such
as AVTCORE, CLUE, ICE, and RTCWEB). In particular, the many uses of SDP
have led to requests for numerous extensions as well as a recognition of
several limitations in the original protocol design. Today, the SDP
protocol is widely deployed and continues to see extensions being defined.

The current aims of the working group include the following:

- Provide SDP signaling support for the Interactive Connectivity
Establishment (ICE) protocol and its extensions. These were originally
defined in MMUSIC, but are now handled by the ICE WG.
- To support the establishment of multi-party multimedia sessions for
RTCWEB based implementations, MMUSIC provides SDP signaling support for
a number of extensions required by RTCWEB. The MMUSIC WG will seek a
balanced trade-off between general applicability of such extensions
versus RTCWEB specific usage.
- Various other extensions to SDP may be pursued to remedy the most
urgent of SDP's shortcomings. These include updates to the SDP
specification itself and missing IANA registrations.
- With the exception of the items listed above, only extensions within
the existing SDP framework will be done.
- Maintain the specification of the (revised) Real Time Streaming
Protocol (RTSP) as needed.

The MMUSIC work items will be pursued in close coordination with other
IETF WGs including AVTCORE, CLUE, ICE, RTCWEB and SIPCORE, as well as
others where appropriate.