[rmcat] Doubt regarding REMB and SSRCs
Iñaki Baz Castillo <ibc@aliax.net> Wed, 01 March 2017 13:49 UTC
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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Wed, 01 Mar 2017 14:49:31 +0100
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Subject: [rmcat] Doubt regarding REMB and SSRCs
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Hi, It's not clear for me what the "SSRC feedback" entries in the REMB message mean. According to the draft [*]: -------------------- Num SSRC (8 bits): Number of SSRCs in this message. SSRC feedback (32 bits): Consists of one or more SSRC entries which this feedback message applies to. -------------------- At the same time, the draft says: --------------------- This feedback message is used to notify a sender of multiple media streams over the same RTP session of the total estimated available bit rate on the path to the receiving side of this RTP session. --------------------- The meaning of "RTP session" is hard to explain nowadays, so I'll assume it means "a media transport" (which in the context of WebRTC points to an ICE established "connection" which can carry multiple SSRC streams). So, if for example Alice is receiving audio (SSRC 1111) and video (SSRC 2222) over a BUNDLEd transport, and assuming Alice can just receive 500 kbits/s, how should REMB messages generated by Alice look like? Should these REMB messages contain both SSRC 1111 and SSRC 2222 and indicate 500000 as media bit rate? What would happen if Alice sends a REMB just including the SSRC 1111 and 500000 as media bit rate? Should Bob limit its audio bitrate up to 500kbit/s and send whatever he wants regarding its video stream? Thanks a lot. [*] https://tools.ietf.org/html/draft-alvestrand-rmcat-remb-03 -- Iñaki Baz Castillo <ibc@aliax.net>
- [rmcat] Doubt regarding REMB and SSRCs Iñaki Baz Castillo
- Re: [rmcat] Doubt regarding REMB and SSRCs Iñaki Baz Castillo