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Re: [MMUSIC] SDP connection attribute optional [was: DTLS-SDP: TLS support added]

Roman Shpount <roman@telurix.com> Mon, 10 April 2017 19:49 UTC

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From: Roman Shpount <roman@telurix.com>
Date: Mon, 10 Apr 2017 15:49:37 -0400
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To: Christer Holmberg <christer.holmberg@ericsson.com>
Cc: "mmusic-chairs@ietf.org" <mmusic-chairs@ietf.org>, "mmusic (E-mail)" <mmusic@ietf.org>, Ben Campbell <ben@nostrum.com>
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Subject: Re: [MMUSIC] SDP connection attribute optional [was: DTLS-SDP: TLS support added]
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On Mon, Apr 10, 2017 at 3:40 PM, Christer Holmberg <
christer.holmberg@ericsson.com> wrote:

> I suggest to add something like the following, to make sure it’s clear:
>
>
>
> *“An offerer and answerer MUST use the SDP 'connection' attribute even if
> it*
>
> * is known that both support the SDP 'tls-id' attribute.*
>
> *  NOTE: As defined in [RFC4145], if the SDP 'connection' attribute is not
> explicitly*
>
> *  present, the implicit default value is 'new'.”*
>

If third party call control is used it is not known that the same end
points are communicating. Because of this it is never quite known what is
supported by the remote end point when offer is generated. Because of this
I would prefer this language to say that "Offerers should not make
assumptions about the support of SDP 'tls-id' attribute and MUST always use
SDP 'connection' attribute. To avoid ambiguity, answerers MUST always use
SDP 'connection' attribute as well.  NOTE: As defined in [RFC4145], if the
SDP 'connection' attribute is not explicitly present, the implicit default
value is 'new'."

Regards,
_____________
Roman Shpount

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