Re: [rtcweb] Symmetric RTP and uni-directional media streams

Christer Holmberg <> Thu, 01 September 2011 16:10 UTC

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From: Christer Holmberg <>
To: Harald Alvestrand <>, Bernard Aboba <>
Date: Thu, 01 Sep 2011 18:12:02 +0200
Thread-Topic: [rtcweb] Symmetric RTP and uni-directional media streams
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Subject: Re: [rtcweb] Symmetric RTP and uni-directional media streams
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I can't of course speak on behalf of others, but at least in IETF I assume one reason why people haven't said anything is simply because they haven't read the API :)



From: Harald Alvestrand []
Sent: 1. syyskuuta 2011 18:52
To: Bernard Aboba
Cc: Christer Holmberg;
Subject: Re: [rtcweb] Symmetric RTP and uni-directional media streams

On 09/01/11 16:35, Bernard Aboba wrote:
I think Christer's question related to the following text from the W3C WEBRTC editor's draft ( 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]<>
Yes, as Christer knows, I think that's a broken design, have argued against it, and we're not implementing to it.
It's a bit strange of me of all people to flash the interoperability card, but this is not interoperable with other RTP usages either.