Re: [rtcweb] Quick comments on draft-roach-rtcweb-glareless-add-00

[Cullen Jennings <[e-mail]>]

On May 9, 2013, at 8:21 PM, Paul Kyzivat <[e-mail]> wrote:

> On 5/9/13 11:39 AM, Adam Roach wrote:
>> On 5/9/13 10:18, Paul Kyzivat wrote:
>>> On 5/8/13 5:18 PM, Adam Roach wrote:
>>>> 
>>>> What I was trying to say above is that the only information you would
>>>> need to convey is literally one, two, or three <mediatype,ordinality>
>>>> pairs. You don't say what you're planning to do with them, just that you
>>>> need them.
>>> 
>>> How is that possibly enough? What codecs and codec parameters/optons?
>>> What bandwidth? What bundling options? The list goes on.
>> 
>> I apologize. I must have done a really poor job in the prose in my
>> draft, since I clearly didn't communicate the fundamental mechanism that
>> I had in mind at all.
>> 
>> Let me try with a ladder diagram to see whether that helps illuminate
>> what I'm proposing.
>> 
>> 
>> Offerer                             Answerer
>>    |                                    |
>>    |<----------Solicitation-------------|
>>    |  (I need 1 new audio 1 new video)  |
>>    |                                    |
>>    |                                    |
>>    |-------------SDP Offer------------->|
>>    | (Contains two more m-line sections |
>>    | than the current session; one      |
>>    | audio, one video. Both recvonly.)  |
>>    |                                    |
>>    |                                    |
>>    |<------------SDP Answer-------------|
>>    | (Makes use of the two new m-line   |
>>    | sections by populating them with   |
>>    | codec parameters, options, ssrc    |
>>    | bandwidth, bundling, etc, etc.)    |
>> 
> 
> Yeah, I figured that from the last message. But the answer is constrained by the offer. So the answer may only have codecs that are listed in the offer.
> 
> I guess the offerer can just include everything it is capable of supporting. But that would be especially unpleasant

it seem to me that we all the same problems in the initial offer. The whole idea of an Offer/Answer is the offer has more or less has everything you support or are willing to do so I don't really see that being a big problem here.