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Re: [rtcweb] Reasons (not?) to multiplex audio with video

Bala Pitchandi <Bala@vidyo.com> Tue, 26 July 2011 21:48 UTC

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From: Bala Pitchandi <Bala@vidyo.com>
To: Ross Finlayson <finlayson@live555.com>, "rtcweb@ietf.org" <rtcweb@ietf.org>
Date: Tue, 26 Jul 2011 17:48:30 -0400
Thread-Topic: [rtcweb] Reasons (not?) to multiplex audio with video
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Subject: Re: [rtcweb] Reasons (not?) to multiplex audio with video
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> 1/ Apple's "FaceTime".  OK, this is not browser-based (although with a bit of work it probably could have been), but it does use RTP.  Is it using separate ports for audio and video (and two more for RTCP)? 
> If so, has NAT traversal been a problem, and would it have been beneficial to have been able to reduce the number of ports used?  (Is Dave Singer on this mailing list?)

I believe FaceTime multiplexes audio & video on to the same port. In fact, it even multiplexes the signaling on to the same port. See: http://blog.roychowdhury.org/2010/06/25/facetime-on-iphone-4-vanilla-unencrypted-stun-and-sip/

-- Bala

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