Re: [rtcweb] Making progress on the signaling discussion (NB: Action items enclosed!)

Harald Alvestrand <harald@alvestrand.no> Wed, 12 October 2011 12:48 UTC

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Date: Wed, 12 Oct 2011 14:42:17 +0200
From: Harald Alvestrand <harald@alvestrand.no>
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To: Tim Panton <tim@phonefromhere.com>
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Cc: rtcweb@ietf.org
Subject: Re: [rtcweb] Making progress on the signaling discussion (NB: Action items enclosed!)
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On 10/12/11 14:36, Tim Panton wrote:
>
>
>>
>
> Lets assume we use a subset/variant of SDP as a codec capability 
> description 'language' - (i.e. we won't be using the parts that relate 
> to network properties).
(note - I'm not making that assumption)
>
> The question then becomes: 'Is current SDP usage so idiosyncratic that 
> it is difficult/impossible to describe a mapping to/from (say) a set 
> of javascript objects which would work for all existing and future 
> codecs that play by the current rules?'
>
The problem I see there is "future codecs".

Anyone who specifies anything that they know has to be handled in SIP 
for some reason tend to specify their mapping to SIP in great detail, 
but not necessarily with a great deal of formality.

I couldn't say offhand what the "current rules" are. That makes it hard 
to make a parser/generator that is guaranteed to handle all valid examples.

             Harald