Hello, „In Plan B, one “m=” section of SDP is used for video and audio respectively. If an application sends or receives multiple media tracks of the same media type, multiple “a=ssrc” lines are listed in the same “m=” section. In contrast, with Unified Plan every single media track is assigned to a separate “m=” section. If you use multiple media tracks, multiple “m=” sections are created. From e.g. https://www.callstats.io/blog/what-is-unified-plan-and-how-will-it-affect-y… Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com *From:* sr-dev <sr-dev-bounces(a)lists.kamailio.org> *On Behalf Of *Daniel-Constantin Mierla *Sent:* Tuesday, May 19, 2020 7:46 AM *To:* Kamailio (SER) - Development Mailing List <sr-dev(a)lists.kamailio.org>rg>; M S <shaheryarkh(a)gmail.com> *Subject:* Re: [sr-dev] RTPEngine - Support for Unified Plan SDP Format Hello, what are the differences in building the SDP for the two types (plan-b vs unified-plan)? Can you (someone else) summarize? it will be useful to see what can be done for sdpops module. On the other hand, rtpengine gets full SDP body from Kamailio and returns the new full SDP back, so here I do not think Kamailio's RTP engine needs update, maybe new flags to control if the change should be done or not (e.g., between two webrtc endpoints, one with old format and the other with the new format). Cheers, Daniel On 17.05.20 06:31, M S wrote: Hi, Since Chrome M72, the default format of SDP generated by Chrome's WebRTC stack has been changed to "unified-plan" instead of Google's old "plan-b" format, which has no been deprecated and planned to be removed sometime in mid 2020. Here are more details about it. https://webrtc.org/getting-started/unified-plan-transition-guide This poses a big problem for non-web WebRTC clients, servers and proxies (such as RTPEngine) which will stop working as soon as Google Chrome removes support for legacy "plan-b" SDP format. In kmaialio's RTPEngine module, so far I have seen no support for this new "unified-plan" SDP format. Are there any support planed for future? Meanwhile, if there any way to add support for it in Kamailio via SDP manipulation e.g. SDPOPS module etc. Thank you. -- Muhammad Shahzad Shafi Tel: +49 176 24 73 85 20 _______________________________________________ Kamailio (SER) - Development Mailing List sr-dev(a)lists.kamailio.org https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-dev -- Daniel-Constantin Mierla -- www.asipto.com www.twitter.com/miconda -- www.linkedin.com/in/miconda Funding: https://www.paypal.me/dcmierla