Hi Pavlos, Sending two media descriptions signals the desire to establish two media streams. Messenger does not support two media streams of audio type. It does support more than one stream but with different data types (e.g. one audio, one video and one data stream). What happens is that Messenger accepts your proposal for the first stream ( using G.711 ULaw) and rejects the second stream (since it can't do two audio streams simultaneously) by putting zero in the port (the standard SDP way of rejecting a proposed stream). If your intention was to really open TWO audio streams then I am afraid that you can not do that with Messenger (even then, your SDP offer looks wrong ; it should have different ports in the media descriptions). If however you want to advertise your capability of doing any one of the two codecs for an audio stream than, the right way to do it would be to have one media description with a format list with more payload types (and rtpmap attributes) like this :
m=audio 2074 RTP/AVP 0 8 a=rtpmap:0 PCMU/8000 a=rtpmap:8 PCMA/8000 Hope this helps, Antonis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Paraskevopoulos Pavlos Sent: Wednesday, December 18, 2002 4:44 PM To: sip-implementors Subject: [Sip-implementors] MSN Messenger call problem Hi, I try to establish a call with the msn messenger. Sending the following invite.... Session Initiation Protocol Request-Line: INVITE sip:146.124.120.221:10891 SIP/2.0 Message Header Max-Forwards: 10 Record-Route: <sip:[EMAIL PROTECTED];branch=0> Via: SIP/2.0/UDP 146.124.20.189;branch=z9hG4bKb824.76b7a4e3.0 Via: SIP/2.0/UDP 146.124.121.233:5060 From: 4341 <sip:[EMAIL PROTECTED]>;tag=29030 To: <sip:[EMAIL PROTECTED]> Call-ID: [EMAIL PROTECTED] CSeq: 1 INVITE Contact: <sip:[EMAIL PROTECTED]:5060> Content-Type: application/sdp User-Agent: netPhone-010104 Content-Length: 147 Session Description Protocol Session Description, version (v): 0 Owner/Creator, Session Id (o): ppar 2697 2697 IN IP4 146.124.121.233 Session Name (s): Our Conversation Connection Information (c): IN IP4 146.124.121.233 Time Description, active time (t): 0 0 Media Description, name and address (m): audio 2074 RTP/AVP 0 Media Description, name and address (m): audio 2074 RTP/AVP 8 I get the following 200 response.... Session Initiation Protocol Status-Line: SIP/2.0 200 OK Message Header Via: SIP/2.0/UDP 146.124.20.189;branch=z9hG4bKb824.76b7a4e3.0 Via: SIP/2.0/UDP 146.124.121.233:5060 From: 4341 <sip:[EMAIL PROTECTED]>;tag=29030 To: <sip:[EMAIL PROTECTED]>;tag=5fc8142e-126a-11d7-87a0-00d0596a8d2f Call-ID: [EMAIL PROTECTED] CSeq: 1 INVITE Record-Route: <sip:[EMAIL PROTECTED];branch=0> Contact: <sip:146.124.120.221:10891> User-Agent: Windows RTC/1.0 Content-Type: application/sdp Content-Length: 176 Session Description Protocol Session Description, version (v): 0 Owner/Creator, Session Id (o): Standard 0 0 IN IP4 146.124.120.221 Session Name (s): Our Conversation Connection Information (c): IN IP4 146.124.120.221 Bandwidth Information (b): CT:1000 Time Description, active time (t): 0 0 Media Description, name and address (m): audio 58772 RTP/AVP 0 Media Attribute (a): rtpmap:0 PCMU/8000 Media Description, name and address (m): audio 0 RTP/AVP 0 I have a question regarding the Media description part of the SDP body. I send two media Dscriptions Media Description, name and address (m): audio 2074 RTP/AVP 0 Media Description, name and address (m): audio 2074 RTP/AVP 8 and the I receive as a response, two media Descriptions with the same payload but with different RTP port to use. Is there anything wrong with my invitation , or with the setings of MSN messenger? Thanks in advance. \\\\\\|////// \\ - - // ( @ @ ) ---oOOo-(_)-oOOo------------------------------------ * Paraskevopoulos Pavlos. tel +30 1 66 74 342 * Senior Software Engineer. fax +30 1 68 74 446 * MailTo : [EMAIL PROTECTED] * * RESEARCH & DEVELOPMENT GENERAL DIVISION * TERMINAL EQUIPMENT DEPARTMENT * * INTRACOM S.A. http://www.intracom.gr *---------------------------------------------------- * HELLENIC TELECOMMUNICATIONS & ELECTRONICS INDUSTRY * Markopoulou Ave, 190 02 Peania, * Greece ----------Oooo------------------------------------------- oooO ( ) ( ) ) / \ ( (_/ \_) _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
