Hi, we've found out that our server changed the whole SDP before giving it to the callee (No matter how we changed it, it was always the same). The SIP server we used is 3CX Phone System, from Microsoft, which I guessed is made to work with 3CX softphone, so the replaced SDP does the work for this. We found another free and more "transparent" SIP server, which ias a lot easier, more user-friendly, it's called minisipserver. Now the SDP passes, and the two media lines are established, and we can talk and hear each other through the audio line, just as normal. But we added a dummy video codec (which doesn't exist), rtpmap:2 BITMAP/16000, before the telephone-events line. Otherwise, it crashed at the media session creation. But if you say that telephony-events attribute is not mandatory, we'll try to remove both. We understand what the attributes connection, rtcp and sendrecv (media direction) are for, but what about fmtp and rtpmap ? We have a vague idea, since the rtpmap attribute of the already created audio "m" line contains info about a codec, like PCMU or PCMA, and a supported bitrate. There's also the telephony-events that we're not sure about. If you could just give us a little hint on that, and we'll keep up, thanks Fran?ois Roseberry Date: Wed, 25 Mar 2009 15:40:24 +0000 From: bennylp@xxxxxxxxx To: pjsip at lists.pjsip.org Subject: Re: SDP Question 2009/3/25 Fran?ois Roseberry <frank_pharaoh05 at hotmail.com> Thanks for the quick reply, Here's the Wireshark capture. As you can see, we added a connection line in the second media, even though it's optional. That should be okay, it will be picked up if it's present. And we don't have any video codec. I want to know if we're obliged to have at least one ? That's fine too. You can also omit the telephone-event and just put empty format list in the m=video line, which is valid according to the spec. At glance, the SDP looks okay, I couldn't find anything wrong with it either. Perhaps the best way to troubleshoot this is to put breakpoint on pjmedia_sdp_parse() function in pjmedia/sdp.c, and trace it step by step to know what the parser thinks about it. I'll do that as soon as time permits. cheers Benny Fran?ois Roseberry Messenger vous offre des tonnes de nouvelles fonctions qui rendent le clavardage encore plus plaisant Cliquez ici pour en savoir plus. _______________________________________________ Visit our blog: http://blog.pjsip.org pjsip mailing list pjsip at lists.pjsip.org http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org _________________________________________________________________ R?inventez comment vous restez en contact avec le nouveau Windows Live Messenger. http://go.microsoft.com/?linkid=9650737 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20090325/da584a78/attachment.html>
