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

Harald Alvestrand <harald@alvestrand.no> Wed, 12 October 2011 11:39 UTC

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Date: Wed, 12 Oct 2011 13:39:01 +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 12:31, Tim Panton wrote:
>
> On 12 Oct 2011, at 11:00, Harald Alvestrand wrote:
>
>> On 10/12/11 11:46, Neil Stratford wrote:
>>> On Wed, Oct 12, 2011 at 10:01 AM, Harald Alvestrand 
>>> <harald@alvestrand.no <mailto:harald@alvestrand.no>> wrote
>>>
>>>     One of the worries I have with doing a "low level spec"
>>>     unconstrained by our present competence (ignorance?) in  is that
>>>     I'm reasonably sure we have the knowledge to generate and parse
>>>     SDP, because the codebases we are building on already generate
>>>     and parse SDP, and the information present there is enough to
>>>     set up calls, because we're already setting up calls using that
>>>     information.
>>>
>>>     I'm less sure of our "getting things right" if we start off by
>>>     describing the capabilities and control knobs to be exposed in
>>>     an unconstrained API.
>>>
>>>
>>> As a counter argument, those very same codebases that generate and 
>>> parse SDP also contain internal APIs that look a lot like a low 
>>> level spec API, and the information they present is enough to 
>>> generate and parse SDP and set up calls.
>>>
>>> Maybe we don't like those APIs and perhaps they expose too much as 
>>> they were never intended to be made public, but they do exist already.
>> Yup. And I suspect they're all subtly different.
>>
>
> You could look at that in a positive light -
> as evidence that there are multiple ways to solve this problem and deduce:
> a) it isn't impossibly hard
> b) there isn't one 'correct' way of doing it.
>
> Which would lead me back to specifying as _little_ as possible and 
> letting innovation take place.
>
We have to specify enough for interoperation in at least the use cases 
of the scenarios document.
In enough detail for interoperation to happen.

That could turn out to be a lot, especially if we can't point to 
existing specs and say "use that".

               Harald