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Re: [rtcweb] RTP Usage: Is RTP Retransmission REQUIRED or RECOMMENDED

Martin Thomson <martin.thomson@gmail.com> Thu, 05 July 2012 15:47 UTC

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Date: Thu, 05 Jul 2012 08:48:02 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Roman Shpount <roman@telurix.com>
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] RTP Usage: Is RTP Retransmission REQUIRED or RECOMMENDED
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On 4 July 2012 12:39, Roman Shpount <roman@telurix.com> wrote:
> Unless we have a SIP end point that supports DTLS-SRTP  and ICE, understands
> AVPF profile, and knows how to negotiate RTP retransmissions and other RTP
> extensions, [...]

I think that this is a little pessimistic.  SRTP with SDES is still a
viable option, for this reason.  The SIP endpoint can implement
ICE-lite and still interoperate.  AVPF senders can interoperate with
AVP receivers unless you have some strange business going on at the
AVP end.  And RTP retransmission is easy to claim support for without
actually supporting (either the NACKs or the retransmissions got lost,
I don't know which, sorry).

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