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

Christer Holmberg <christer.holmberg@ericsson.com> Thu, 01 September 2011 16:10 UTC

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From: Christer Holmberg <christer.holmberg@ericsson.com>
To: Harald Alvestrand <harald@alvestrand.no>, Bernard Aboba <bernard_aboba@hotmail.com>
Date: Thu, 1 Sep 2011 18:12:02 +0200
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Subject: Re: [rtcweb] Symmetric RTP and uni-directional media streams
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Hi,

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 :)

Regards,

Christer

________________________________
From: Harald Alvestrand [mailto:harald@alvestrand.no]
Sent: 1. syyskuuta 2011 18:52
To: Bernard Aboba
Cc: Christer Holmberg; rtcweb@ietf.org
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 (http://dev.w3.org/2011/webrtc/editor/webrtc.html) Section 4:

All streams represented by MediaStream<http://dev.w3.org/2011/webrtc/editor/webrtc.html#mediastream> objects must be marked as "sendonly" by the peer that initially adds the stream to the session. The PeerConnection<http://dev.w3.org/2011/webrtc/editor/webrtc.html#peerconnection> API does not support bidirectional ("sendrecv") audio or video media streams. [SDPOFFERANSWER]<http://dev.w3.org/2011/webrtc/editor/webrtc.html#refsSDPOFFERANSWER>
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.