Re: [MMUSIC] DTLS-SRTP client/server role negotiation

Gustavo García <ggb@tokbox.com> Wed, 01 May 2013 21:11 UTC

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From: Gustavo García <ggb@tokbox.com>
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Date: Wed, 01 May 2013 14:10:46 -0700
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To: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Cc: mmusic@ietf.org
Subject: Re: [MMUSIC] DTLS-SRTP client/server role negotiation
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I saw it, but that is all about TCP client/server role and not DTLS client/server role.   Are we supposed to use the same "setup" attribute for dtls role negotiation even if it is over UDP?

I think there is no reason to tie TCP and DTLS roles, but perhaps I'm misunderstanding something.

On 01/05/2013, at 13:56, Paul Kyzivat wrote:

> On 5/1/13 2:26 PM, Gustavo García wrote:
>> RFC5764 (DTLS-SRTP) states that "Which side is the DTLS client and which side is the DTLS server must be established via some out-of-band mechanism such as SDP."
>> 
>> What is the specification on how to signal that in SDP?
>> 
>> Specifically in case of 3pcc where both endpoints are SDP offerers which one should take the client and server roles for DTLS?    Should we tie that role to ICE controlled/controlling roles or should we negotiate it in the SDP somehow?
> 
> See RFC4145.
> 
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