[R-C] [Iccrg] Re: Timely reaction time (Re: Comments on draft-alvestrand-rtcweb-congestion-01)

[Michael Welzl]

Argh, yes, I guess this one letter was the cause of a  
misunderstanding... Thanks!

Sent from my iPod

On Apr 1, 2012, at 23:56, Lachlan Andrew <lachlan.andrew at gmail.com>  
wrote:

> Greetings Michael,
>
> Are you saying you need an emergency "brake" (i.e., slowing down)
> rather than emergency "break" (i.e., termination, with or without a
> restart later)?
>
> Cheers,
> Lachlan
>
> On 30 March 2012 21:17, Michael Welzl <michawe at ifi.uio.no> wrote:
>>
>> On Mar 30, 2012, at 10:33 AM, Harald Alvestrand wrote:
>>
>>> On 03/29/2012 01:55 PM, Michael Welzl wrote:
>>>>
>>>>
>>>>
>>>>> Section 4: par 3, "This algorithm is run every time a receive  
>>>>> report
>>>>> arrives..." => so in case of severe congestion, when nothing  
>>>>> else arrives,
>>>>> this algorithm waits for 2 * t_max_fb_interval... so can we rely  
>>>>> on the
>>>>> mechanism to react to this congestion after roughly an RTO or  
>>>>> not? (sounds
>>>>> like not)  Is that bad?  (I guess)
>>>>>
>>>>> There is a need for some emergency break mechanism if no  
>>>>> feedback gets
>>>>> through.
>>>>
>>>>
>>>> I totally agree - what I meant is, it isn't clear to me if that  
>>>> emergency
>>>> break is activated in time or too late. It should be in time  
>>>> (i.e. after
>>>> roughly an RTO).
>>>
>>> This seems to be a subject that should be discussed in the context  
>>> of the
>>> circuit-breakers draft: What kind of response time is appropriate  
>>> for such a
>>> mechanism, and why?
>>
>>
>> I think not: we're talking about two kinds of situations here. The  
>> context
>> here is: there was congestion, we should react to it within an RTO  
>> (and have
>> an "emergency break" to always do that - but maybe that term was
>> misleading). The circuit-breakers draft is about a much more serious
>> condition (such as persistent congestion), warranting a much more  
>> serious
>> reaction (terminating the connection).
>>
>> Cheers,
>> Michael
>
>
>
> -- 
> Lachlan Andrew  Centre for Advanced Internet Architectures (CAIA)
> Swinburne University of Technology, Melbourne, Australia
> <http://caia.swin.edu.au/cv/landrew>
> Ph +61 3 9214 4837