Hi, I am trying to implement a SIP-based multi-point conferencing based on "Centralized Signaling, Distributed Media" model (draft-ietf-sipping-conferencing-models-01.txt). In this model, each participant UA gets updated SDP descriptions using "re-INVITE" whenever a user enters to (or exits from) the conference. If the number of participants becomes more than two, then the re-INVITE message should contain two or more SDP descriptions. For example, if user A, B and C are in the conference, then a re-INVITE to user A should contain two SDP description, one for user B and the other for user C.
My question here is: how to describe multiple SDP descriptions in the content body of INVITE (or 200 OK) message? Do we just concatenate them? For example, if the conference server sends re-INVITE to user A with SDPs of user B and C, the content body will look like this: v=0 o=user-b 0 0 IN IP4 192.168.1.100 s=session c=IN IP4 192.168.1.100 b=CT:1000 t=0 0 m=audio 30001 RTP/AVP 0 a=rtpmap:0 PCMU/8000 v=0 o=user-c 0 0 IN IP4 192.168.1.101 s=session c=IN IP4 192.168.1.101 b=CT:1000 t=0 0 m=audio 30002 RTP/AVP 0 a=rtpmap:0 PCMU/8000 Is this correct implementation for multiple SDP sessions? I could not find any descriptions in RTF 3261 that say UA should handle multiple SDP sessions. Thanks, Seonman _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
