[e2e] Congestion control as a hot topic in IETF
detlef.bosau at web.de
Wed Mar 20 05:02:03 PDT 2013
Am 20.03.2013 00:06, schrieb Ted Faber:
> On Tue, Mar 19, 2013 at 10:37:54PM +0100, Detlef Bosau wrote:
>> However, what you wrote is no contradiction to what I said?
> You're talking about some mechanisms used to solve the problem those
> other folks described. That isn't a contradiction, but I think you're
> missing the forest for the trees.
And so, it is not reasonable to review the purpose of congestion control?
Sometimes, I don't have the impression that I miss the forest for the
trees, but we argue for different forests here.
Forest 1: Stability. (Nearly forgotten, hardly mentioned in many PhD
theses I read throughout the last decade, the only .)
BTW: This forest is quite interesting, because from the system theory
perspective, the often so called "buffer bloat problem" may well be a
(BTW2: This forest is mentioned in the congavoid paper in a footnote - I
strongly suspect this one of the most ignored footnotes in computer
Forest 2: A reasonable trade off between work conservation on the one
hand and acceptable delay on the other. IIRC this is Raj Jain's forest.
Forest 3: Sharing and allocation of resources. IIRC the most
comprehensive, if to my understanding not that widely accepted, work in
this direction is Keshav's PhD thesis. (Sorry for me sending this twice,
I'm to stupid to correctly send an e-mail....) Unfortunately, I only
read some of Keshav's papers and I'm still to read the whole thesis.
Forest 4: Finding the right trade-offs. From Dave Reed I know that he is
strongly focussed on the overall delay. Some guys criticize the pure
focus on throughput and mostly work conservation. (I'm sometimes told I
must not talk about German politics here, but the "idle is evil"
paradigm is the very core of quite some politics, be it the working
morale of evangelic chistian churches or the work of the well known
sociologist Max Weber.)
The quotient (throughput / delay) is at least a possible trade off here.
Perhaps, it is neither the only one nor the best one. But when some guys
argue with "knee" and "cliff" here, they refer to the well known picture
IIRC it was Joe Touch wo said (some time ago) the Internet may not give
as always the resources we want, but we always get the resources we need.
Actually, I see two extremes: Dedicated resources e.g. as in the IntServ
architecture (which is, to a certain degree, nothing else as a
reinvented circuit switching system) on the one hand, "chaotic swarm
intelligence" and collective praying on the other.
Now, the very purpose of our discussion, please correct me if I'm wrong,
is to find a reasonable way in the middle - and that's what we are used
to call "Best Effort".
70565 Stuttgart Tel.: +49 711 5208031
mobile: +49 172 6819937
detlef.bosau at web.de http://www.detlef-bosau.de
More information about the end2end-interest