Re: [rtcweb] RTP Usage: Is RTP Retransmission REQUIRED or RECOMMENDED

Colin Perkins <csp@csperkins.org> Fri, 29 June 2012 15:26 UTC

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From: Colin Perkins <csp@csperkins.org>
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Date: Fri, 29 Jun 2012 16:26:55 +0100
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To: Cullen Jennings <fluffy@iii.ca>
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Subject: Re: [rtcweb] RTP Usage: Is RTP Retransmission REQUIRED or RECOMMENDED
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Cullen,

You're being asked what RTP tools the browser needs to implement, not what RTP tools you want use with audio or video codecs. 

Colin


On 29 Jun 2012, at 16:11, Cullen Jennings wrote:
> Right - so on the question of it retransmission is mandatory to implement for audio codec, I am on a definitely "No". The bulk of systems today do not do it and work fine. Vendors can easily choose to do if they want in an interoperable way with out it being MTI. Why we should add a bunch of stuff in to version 1 of this that we can live without is beyond me. This is how IPv6 got big and hard, by everyone taking their favorite technology and attaching it to v6. I don't even want it as RECOMMENDED for audio - I see it as OPTIONAL. 
> 
> I probably feel differently about video. 
> 
> 
> On Jun 28, 2012, at 23:43 , Magnus Westerlund wrote:
> 
>> On 2012-06-28 16:36, Cullen Jennings wrote:
>>> 
>>> I think you need to separate this for audio and video and be far more
>>> specific about what type of retransmit ion you are talking about. In
>>> many cases the retransmit ion schemes for audio make the end suer
>>> experience worse.
>> 
>> I am not disagreeing unless the RTT is really low.
>> 
>> What I am asking the WG is if RTP retransmission is a RECOMMENDED or
>> REQUIRED feature in the toolbox that an WebRTC end-point supports. This
>> says nothing on when you select to use it and on which media. If we want
>> to include such recommendations we can do it. In fact the RTP usage
>> draft has a bit on text discussing the issue with RTT.
>> 
>> Cheers
>> 
>> Magnus
>> (As WG chair)
>> 
>>> 
>>> On Jun 27, 2012, at 24:36 , Magnus Westerlund wrote:
>>> 
>>>> WG,
>>>> 
>>>> We had a discussion at the interim if RTP Retransmission is to be 
>>>> considered REQUIRED or RECOMMENDED to implement. I would like to
>>>> see if we can first have some discussion on this topic before
>>>> moving on to see if we can get a consensus here on the mailing
>>>> list.
>>>> 
>>>> Please provide your views on this topic.
>>>> 
>>>> Cheers
>>>> 
>>>> Magnus Westerlund (As Chair and document editor)
>>>> 
>>>> 
>>>> ----------------------------------------------------------------------
>>>> 
>>>> 
>> Multimedia Technologies, Ericsson Research EAB/TVM
>>>> ----------------------------------------------------------------------
>>>> 
>>>> 
>> Ericsson AB                | Phone  +46 10 7148287
>>>> Färögatan 6                | Mobile +46 73 0949079 SE-164 80
>>>> Stockholm, Sweden| mailto: magnus.westerlund@ericsson.com 
>>>> ----------------------------------------------------------------------
>>>> 
>>>> 
>>>> 
>>>> 
>> _______________________________________________
>>>> rtcweb mailing list rtcweb@ietf.org 
>>>> https://www.ietf.org/mailman/listinfo/rtcweb
>>> 
>>> 
>> 
>> 
>> -- 
>> 
>> Magnus Westerlund
>> 
>> ----------------------------------------------------------------------
>> Multimedia Technologies, Ericsson Research EAB/TVM
>> ----------------------------------------------------------------------
>> Ericsson AB                | Phone  +46 10 7148287
>> Färögatan 6                | Mobile +46 73 0949079
>> SE-164 80 Stockholm, Sweden| mailto: magnus.westerlund@ericsson.com
>> ----------------------------------------------------------------------
>> 
>> 
>> 
> 
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-- 
Colin Perkins
http://csperkins.org/