Hi Paul, I am seeing an Interop issue where a vendor is adding Fax to the existing audio call by sending this SDP in a reINVITE. For obvious reasons this reINVITE is rejected.
But I wanted to know if this can be allowed in any case. Thanks, Puneet -----Original Message----- From: Paul Kyzivat [mailto:pkyzi...@alum.mit.edu] Sent: Monday, July 15, 2013 11:27 PM To: sip-implementors@lists.cs.columbia.edu Subject: Re: [Sip-implementors] SDP media line reordering in reINVITE. On 7/15/13 1:45 PM, Kumar, Puneet (Puneet) wrote: > Hi All, > > Is it allowed to change the order of media line in SDP in case an UA sends a > reINVITE? > > Consider a case where call is up with audio. > > m=audio 38646 RTP/AVP 18 > > Now can any UA send following in the SDP: > > m=image 38648 udptl t38 > ... > m=audio 38646 RTP/AVP 8 0 97 > > > As seen above "image' line is added prior to "audio" line. Nominally this is not permitted. BUT, you are permitted to *replace* the first m-line with a new one, and add another. So technically you could do this without violating anything. But this would most likely confuse many peers. At best they might totally reset communication, causing glitches. Why would you want to do this? Thanks, Paul _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
