[Bloat] I feel an urge to update this

Manolis Sifalakis sifalakis.manos at unibas.ch
Sat Sep 27 04:59:31 EDT 2014


A couple of remarks to try and contribute to this discussion, one 
philosophical and one engineering.

The philosophical first. There is a presentation taking place in a room 
and it is possibly at q&a phase. You have several ppl entering the room 
at several time points. What if every person entering the room, 
immediately throws aggressively questions without even having spent time 
to listen and understand the context of presentation and discussion. 
Imagine this happening again and again. Consider what are the chances 
that a meaningful communication and discussion will take place...  or 
simply how would you like that as a person in the audience?

The more technical next. Doubling and tripling IW for short lived 
sessions (each of which will attain --only-- exponential growth in its 
anyway short lifetime) means that a large number of high-freq transient 
components will be added to and removed from the signal that the AQM 
sees (and tries to adapt to). Is that something desired ? Will it 
improve or worsen the way an AQM adapts?  Increasing IW is not only a 
matter of initial value, it also affects the starting growth rate (since 
the relation is not linear).

Manos


On 25/09/14 19:49, Rick Jones wrote:
> On 09/25/2014 10:26 AM, Mikael Abrahamsson wrote:
>> On Thu, 25 Sep 2014, Rick Jones wrote:
>>
>>> Well, there has been such a thing present in TCP from "The Beginning"
>>> though not named as such.  Such a client could always advertise a
>>> smaller (initial) receive window...  One which would allow only IW3 or
>>> whatever value was appropriate.
>>
>> I'm sure there are ways to solve this, but my take from the "TCP people"
>> was that there was not seen to be any need to do anything else than what
>> is done today, ie all TCP connections are self contained and learns
>> nothing from each other.
>
> Well, I cannot speak for "TCP people" but I would think that what a
> given TCP connection decides to advertise as its receive window, and
> whether that decision would need/must depend on what other TCP
> connections have seen are separate, but related.
>
> The main point I wished to make was if one did indeed wish to have a
> receiver behind a slow pipe wish to be able to keep a sender up on a
> fast pipe from actually doing IW10, there was no need for any new signal
> flowing from one end to the other, just setting the receive window
> appropriately.  The TCP stack on the slow-connection device could (and
> perhaps should) be configured for things like (initial) receive windows
> with that in mind.
>
> rick jones
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