Re: [rtcweb] Symmetric RTP and uni-directional media streams
Bernard Aboba <bernard_aboba@hotmail.com> Thu, 01 September 2011 14:34 UTC
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From: Bernard Aboba <bernard_aboba@hotmail.com>
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Subject: Re: [rtcweb] Symmetric RTP and uni-directional media streams
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I think Christer's question related to the following text from the W3C WEBRTC editor's draft (http://dev.w3.org/2011/webrtc/editor/webrtc.html) Section 4: All streams represented by MediaStream objects must be marked as "sendonly" by the peer that initially adds the stream to the session. The PeerConnection API does not support bidirectional ("sendrecv") audio or video media streams. [SDPOFFERANSWER] Date: Thu, 1 Sep 2011 13:30:55 +0200 From: harald@alvestrand.no To: christer.holmberg@ericsson.com CC: rtcweb@ietf.org Subject: Re: [rtcweb] Symmetric RTP and uni-directional media streams On 09/01/11 13:23, Christer Holmberg wrote: Hi, There has been much talk about the usage of symmetric RTP. Also, draft-perkins-rtcweb-rtp-usage suggests that symmetric RTP is required. However, the PeerConnection API currently only supports the establishment of uni-directional streams, so for a single two way communication one needs to create two separate uni-directional streams. So, I assume that one requirement from RTCWEB to W3C will be to add support of the establishment of bi-directional streams to the PeerConnection API. To be precise: I think (and we're implementing) that between two PeerConnections, there will be a small number of *RTP sessions* (ideally one). These will be bidirectional. These will be used for transporting any number of *MediaStreams* (a WEBRTC API concept), each of which corresponds to a CNAME (RTP protocol concept). These are unidirectional. So the right answer is "yes" and "no", as far as I can see. Regards, Christer _______________________________________________ rtcweb mailing list rtcweb@ietf.org https://www.ietf.org/mailman/listinfo/rtcweb _______________________________________________ rtcweb mailing list rtcweb@ietf.org https://www.ietf.org/mailman/listinfo/rtcweb
- [rtcweb] Symmetric RTP and uni-directional media … Christer Holmberg
- Re: [rtcweb] Symmetric RTP and uni-directional me… Harald Alvestrand
- Re: [rtcweb] Symmetric RTP and uni-directional me… Bernard Aboba
- Re: [rtcweb] Symmetric RTP and uni-directional me… Harald Alvestrand
- Re: [rtcweb] Symmetric RTP and uni-directional me… Christer Holmberg