Re: [rtcweb] draft-ietf-rtcweb-rtp-usage-12 Client-to-Mixer Audio Level

Sergio Garcia Murillo <> Wed, 05 March 2014 15:00 UTC

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Date: Wed, 05 Mar 2014 16:00:33 +0100
From: Sergio Garcia Murillo <>
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Subject: Re: [rtcweb] draft-ietf-rtcweb-rtp-usage-12 Client-to-Mixer Audio Level
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El 05/03/2014 13:32, Cullen Jennings (fluffy) escribió:
> I am opposed to mandating that Client-to-Mixer Audio Level RTP header is REQUIRED to be encrypted. It means that we can not really build conferencing system where the mixers do not have access to decrypt the media.
Hi Cullen,

I am not sure I am following you. AFAIK DTLS is only possible to be 
setup between two peers, so in a multiconference solution the mixer will 
anyway have to establish a DTLS/SRTP session which each peer and 
decrypt/encrypt before sending to any of participants in the conference. 
In case of a full meshed conference, there is no need of a mixer at all, 
and the logic could be directly implemented on each of the endpoints.

Am I missing something? Please correct me if I am wrong.

Best regards