Re: [MMUSIC] Offer/Answer PT Questions - text proposal

Roman Shpount <roman@telurix.com> Thu, 25 February 2016 18:12 UTC

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Date: Thu, 25 Feb 2016 13:12:11 -0500
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From: Roman Shpount <roman@telurix.com>
To: Christer Holmberg <christer.holmberg@ericsson.com>
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Subject: Re: [MMUSIC] Offer/Answer PT Questions - text proposal
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On Thu, Feb 25, 2016 at 9:17 AM, Christer Holmberg <
christer.holmberg@ericsson.com> wrote:

> "The scope of a mapping from a particular dynamic payload type number to a
> codec
> (or codec configuration) is for a given RTP media flow direction within a
> session.
> The same dynamic payload type number can be mapped to another codec in
> another RTP
> media flow direction within the same session. The mapping MUST NOT change
> to a different
> coded (or coded configuration) for the duration of a session. Eventhough
> not recommended,
> for a given direction, multiple dynamic payload type numbers can be mapped
> to the
> same codec (or codec configuration).
>

I think MUST NOT is too strict for this rule and SHOULD NOT should be
sufficient. In current implementation this rule is often ignored. The worst
thing that can happen is a small media disruption, but with the careful
implementation, even that will not occur in most use cases.
_____________
Roman Shpount