Multi-stream Media Conferencing

1. Multi-stream Media Conferencing Bo Burman Ericsson AB draft-westerlund-clue-multistream-conference-00

2. IPR Disclosure • For referred drafts • http://datatracker.ietf.org/ipr/1637/ • http://datatracker.ietf.org/ipr/1638/ • http://datatracker.ietf.org/ipr/1639/ • http://datatracker.ietf.org/ipr/1640/ • http://datatracker.ietf.org/ipr/1641/ • http://datatracker.ietf.org/ipr/1644/ draft-westerlund-clue-multistream-conference

3. Purpose • The draft defines a framework and requirements for allowing endpoints with different capabilities to participate in a conference, with each endpoint being able to use as high-quality media as possible draft-westerlund-clue-multistream-conference

4. Overview • A set of selected use cases • Each focusing on an end-point “quality category” • Tries to avoid transcoding • Proposed methods to support the above • RTP usage • Signaling extensions draft-westerlund-clue-multistream-conference

5. Assumptions • End-points of different “quality categories” are present in the same conference • It is desirable to use as high quality media as possible to every end-point • A more capable, higher quality, end-point can always receive a lower quality stream encoded with the same codec draft-westerlund-clue-multistream-conference

6. Low Quality Sender Low RTP Mixer Low Med High draft-westerlund-clue-multistream-conference

7. Medium Quality Sender Med RTP Mixer Low Med High draft-westerlund-clue-multistream-conference

8. Medium Quality Sender Med RTP Mixer Transcoding T Low Med High draft-westerlund-clue-multistream-conference

9. draft-westerlund-avtcore-rtp-simulcast Medium Quality Sender Med Simulcast RTP Mixer Low Med High draft-westerlund-clue-multistream-conference

10. Medium Quality Sender Med Scalable coding RTP Mixer Low Med High draft-westerlund-clue-multistream-conference

11. High Quality Sender • Similar to above • Left as an exercise for the reader draft-westerlund-clue-multistream-conference

12. Multiple High Dual High draft-westerlund-avtcore-max-ssrc-00 Multiple Channel Sender How manysimultaneouschannelscould andshould besent? max-send-ssrc=4 max-recv-ssrc=“many” RTP Mixer max-send-ssrc=“many” An answerer’s max-send-ssrc ≤ offerer’s max-recv-ssrc max-recv-ssrc=1 max-recv-ssrc=1 max-recv-ssrc=1 max-recv-ssrc=2 Low Med High draft-westerlund-clue-multistream-conference

13. High Med Low Low Low draft-westerlund-avtcore-max-ssrc-00 Multi-quality Local Composition AssumingRTP Mixerhas a choiceof qualitiesavailable RTP Mixer *: max-send-ssrc=“many” High: max-recv-ssrc=1Med: max-recv-ssrc=1Low: max-recv-ssrc=3 draft-westerlund-clue-multistream-conference

14. Activespeaker Last Quiet Quiet Quiet Mixer Stream Roles and SSRC Activespeaker Quiet Lastactivespeaker SSRC B SSRC C SSRC D Quiet RTP Mixer Quiet SSRC A SSRC E SSRC M3 (A)SSRC M4 (C)SSRC M5 (E) Mixer SSRC has a“role” and the sourcethat currently holdsthat “role” is identifiedby CSRC SSRC M1 (B) SSRC M2 (D) Mixer SSRC need not changeoften and should be feasibleto tie to a certain decoderresource draft-westerlund-clue-multistream-conference

15. Activespeaker Last Quiet Quiet Quiet Mixer Stream Roles and SSRC Lastactivespeaker Quiet Quiet SSRC B SSRC C SSRC D Activespeaker RTP Mixer Quiet SSRC A SSRC E SSRC M3 (D)SSRC M4 (C)SSRC M5 (E) Mixer SSRC has a“role” and the sourcethat currently holdsthat “role” is identifiedby CSRC SSRC M1 (A) SSRC M2 (B) Mixer SSRC need not changeoften and should be feasibleto tie to a certain decoderresource draft-westerlund-clue-multistream-conference

16. Activespeaker Last Quiet Quiet Quiet Mixer Stream Roles and SSRC Lastactivespeaker Quiet Quiet SSRC B SSRC C SSRC D Activespeaker RTP Mixer Quiet SSRC A SSRC E Mixer SSRC has a“role” and the sourcethat currently holdsthat “role” is identifiedby CSRC SSRC M1 (A) SSRC M2 (B, D, C, E) Some Mixer SSRC maybe “composed” by theMixer and containmultiple CSRC draft-westerlund-clue-multistream-conference

17. Activespeaker Last Quiet Quiet Quiet draft-westerlund-dispatch-stream-selection-00 Receiver Stream Selection Lastactivespeaker Quiet Quiet SSRC B SSRC C SSRC D Activespeaker RTP Mixer Quiet SSRC A SSRC E SSRC M3 (D)SSRC M4 (C)SSRC M5 (E) Receiving end-pointwants to tie a certainsource SSRC to acertain Mixer SSRC(and thus role) SSRC M1 (A) SSRC M2 (B) “Give me D in M1” draft-westerlund-clue-multistream-conference

18. Quiet Last Active Quiet Quiet draft-westerlund-dispatch-stream-selection-00 Receiver Stream Selection Lastactivespeaker Quiet Quiet SSRC B SSRC C SSRC D Activespeaker RTP Mixer Quiet SSRC A SSRC E “Ack” SSRC M3 (A)SSRC M4 (C)SSRC M5 (E) Receiving end-pointwants to tie a certainsource SSRC to acertain Mixer SSRC(and thus overridescontent of that “role”) SSRC M1 (D) SSRC M2 (B) What to do with replaced“roles” is subject to Mixerimplementation and policy;for further consideration Quiet draft-westerlund-clue-multistream-conference

19. Activespeaker Last Quiet draft-westerlund-avtext-rtp-stream-pause-00 Avoid Unused Streams Lastactivespeaker Quiet Quiet SSRC B SSRC C SSRC D “Pause C” Activespeaker RTP Mixer Quiet SSRC A SSRC E “Pause E” Mixer notices that Cand E streams arecurrently not receivedby anyone and decidesto pause them SSRC M1 (A) SSRC M3 (D) SSRC M2 (B) draft-westerlund-clue-multistream-conference

20. Activespeaker Last Quiet draft-westerlund-avtext-rtp-stream-pause-00 Avoid Unused Streams Lastactivespeaker Quiet Quiet SSRC B SSRC C SSRC D “Ack C” Activespeaker RTP Mixer Quiet SSRC A SSRC E “Ack E” C and E streams arepaused and thepauses are ack’ed SSRC M1 (A) SSRC M3 (D) SSRC M2 (B) Paused streams must bepossible to resume veryquickly if they are wantedagain draft-westerlund-clue-multistream-conference

21. Expected Outcome • CLUE is asked to take the presented use cases and proposed solutions into account in its work and when progressing the WG drafts draft-westerlund-clue-multistream-conference