Re: [MMUSIC] Simulcast: Short timelines, draft impending

Harald Alvestrand <harald@alvestrand.no> Thu, 01 October 2015 12:05 UTC

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From: Harald Alvestrand <harald@alvestrand.no>
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Date: Thu, 1 Oct 2015 14:05:45 +0200
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Subject: Re: [MMUSIC] Simulcast: Short timelines, draft impending
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While waiting for the draft, one thing that puzzled me on third reading
through this proposal:

On 09/25/2015 04:34 AM, Adam Roach wrote:
>
>  *
>
>    RIDs can be defined to be unidirectional, so as to allow
>    implementations to signal the ability to send a different number of
>    encodings than they can receive.
>
>  *
>
>    The values for each constraint can be specified to be different in
>    each direction.
>
>
>  *
>
>    The values (that is, identifiers) used for RID are proposed by the
>    offerer in a session, and are symmetric. The RID values in an answer
>    must be a subset of those present in the offer.

I'm a bit confused. How do we have unidirectional but symmetric RIDs?

If the answerer thinks that it is going to need more RIDs than the
offerer proposes, is he required to start a renegotiation to get what he
wants?

Spinoff from that: Is it, in general, possible to add more RIDs at
renegotiation time?

This may be obvious once the draft arrives.