Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in answer if not included in offer?

Roman Shpount <roman@telurix.com> Wed, 22 June 2016 17:56 UTC

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From: Roman Shpount <roman@telurix.com>
Date: Wed, 22 Jun 2016 13:56:17 -0400
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To: Roni Even <ron.even.tlv@gmail.com>
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Cc: Magnus Westerlund <magnus.westerlund@ericsson.com>, "mmusic@ietf.org" <mmusic@ietf.org>, avt@ietf.org, Colin Perkins <csp@csperkins.org>
Subject: Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in answer if not included in offer?
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On Wed, Jun 22, 2016 at 11:35 AM, Roni Even <ron.even.tlv@gmail.com> wrote:

> I am not sure I understand you answer. I was wondering if the answerer can
> ask to receive RTP/RTCP multiplex even if the offer did not include the
> rtp/rtcp-mux attribute by providing in an
>
> A=rtcp the port of for the RTP stream?
>
>
>
Setting a=rtcp to the same port as RTP port effectively can enable one way
RTP/RTCP mux. So, it can work in an answer, but there is a big problem with
it: end point has no way of knowing in advance that a=rtcp will be honored.
It would typically mean that end point should be prepared to work without
RTCP with RTCP sent to the wrong port. I would assume this is not a
solution you would want for any new service.

Regards,
_____________
Roman Shpount