Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiation mechanism

Tim Panton <tim@phonefromhere.com> Thu, 22 September 2011 13:55 UTC

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From: Tim Panton <tim@phonefromhere.com>
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Date: Thu, 22 Sep 2011 06:57:36 -0700
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To: Cullen Jennings <fluffy@cisco.com>
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Subject: Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiation mechanism
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On 22 Sep 2011, at 06:44, Cullen Jennings wrote:

> 
> On Sep 21, 2011, at 2:22 AM, Magnus Westerlund wrote:
> 
>> And why, did you design such a poor glare handling algorithm for SIP? ;-)
> 
> So, the SIP glare algorithm leaves much to be desired, no questions about it. I'm going to claim I was not there at the time until someone proves otherwise then switch my story to I was drunk not stupid. (in fairness we were trying to be backwards compatible with 2543 equipment).

Which is an important lesson for rtcweb, backward compatibility has longterm costs.

At the risk of showing my ignorance - why are we expecting glare to be a problem? 
To my mind glare only happens when you have a locked resource e.g. a busy line
or number . Rtcweb does not contain either of those concepts, what's the resource
that is being competed for here ?

Tim (speaking entirely for his own ignorance)