Re: [R-C] [Iccrg] Re: Timely reaction time (Re: Comments on draft-alvestrand-rtcweb-congestion-01)
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@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@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
I think what you are requesting should be possible with the requirement that the REMB feedback messages should be sent periodically. If none is received within some threshold the sender have to start backing off. REMB are typically sent periodically anyway to be able to probe the channel. /Stefan On Mon, Apr 2, 2012 at 7:44 AM, Michael Welzl <michawe@ifi.uio.no> wrote:
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@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@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<http://caia.swin.edu.au/cv/landrew>
Ph +61 3 9214 4837
______________________________**_________________ Rtp-congestion mailing list Rtp-congestion@alvestrand.no http://www.alvestrand.no/**mailman/listinfo/rtp-**congestion<http://www.alvestrand.no/mailman/listinfo/rtp-congestion>
ok - but anyway now i think that this is generally not the best way to do it ... i'm curious to hear comments about my other mail re sctp... Sent from my iPod On Apr 2, 2012, at 14:04, Stefan Holmer <stefan@webrtc.org> wrote:
I think what you are requesting should be possible with the requirement that the REMB feedback messages should be sent periodically. If none is received within some threshold the sender have to start backing off. REMB are typically sent periodically anyway to be able to probe the channel.
/Stefan
On Mon, Apr 2, 2012 at 7:44 AM, Michael Welzl <michawe@ifi.uio.no> wrote: 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@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@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 _______________________________________________ Rtp-congestion mailing list Rtp-congestion@alvestrand.no http://www.alvestrand.no/mailman/listinfo/rtp-congestion
participants (2)
-
Michael Welzl -
Stefan Holmer