[MMUSIC] DTLS-SRTP client/server role negotiation

Gustavo García <ggb@tokbox.com> Wed, 01 May 2013 18:27 UTC

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

G.