[ih] Why did congestion happen at all? Re: why did CC happen at all?

[Detlef Bosau]

Am 31.08.2014 um 08:14 schrieb Miles Fidelman:
>>
>
> So, you're saying that accidents, rush hours, and construction DON'T
> cause congestion on the A7/E45?  Or that people don't people don't
> adjust their schedules or routes based on traffic reports?
>
> Miles Fidelman
>
>

At least in Germany, wie try (admittedly without sucess) to avoid
traffic congestion by careful planning.

It is always a pity to visit a widow only to tell her: "Unfortunately,
your husband is not coming home today, he was dropped together with his
car this afternoon due to traffic jam near to Frankfurt."

Or, since today it was mentioned that our German secretary of defense,
Ursula von der Leyen, has seven children. I'm not quite sure whether she
is going to solve the problem in the Ukraine by "probing". Send four
children to war, if some are dropped halve the window and send only two,
now the next try is stop and wait....

(Rumour says, that the US Air Force actually assesses traffic control by
probing and drop,  I think the project is conducted near to Ramstein
Airbase.)

Particularly, the ARPANET in its original design offered the necessary
equipment to get along without this nonsense.

Or, if I may quote a sentence which John Day wrote me in a private
communication: "A congestion control scheme, that causes congestion. Funny."

When I started thinking about this issue, I hang on BIC and CUBIC and
thought, why we do this nonsense only to tell a sender on a wireless
link what he already knows, i.e. how fast he may send?

The very reason is that we neglected scheduling. And when we got aware
of this fact, we replaced scheduling by
a) probing and
b) Little's law.

That's the whole story.

And now, we are to overcome the consequences. And we do so for about 25
years. (And we are going still to do so in 25 years, when we don't
attack the basic problem: the lack of proper scheduling and proper flow
control.)

And as the Internet is likely to grow, we will see even more buffers and
even more buffer bloat and perhaps even more heterogeneous networks
which suffer from loss differentiation caused problems and even more
unfairness between mice and elephants and so on.

And as we solve buffer utilization problems by adding more and more
buffer (which can be probed and utilized) the hardware costs increase as
do the round trip times as well.

My only intention is to pursue a different way of thinking here. No
more, no less. (However, we are that brainwashed by these nonsense PhD
projects on "congestion control" who attempt to keep a dead mummy alive,
that we rather sacrifice the world than our probing/dropping nonsense.)

-- 
------------------------------------------------------------------
Detlef Bosau
Galileistraße 30   
70565 Stuttgart                            Tel.:   +49 711 5208031
                                           mobile: +49 172 6819937
                                           skype:     detlef.bosau
                                           ICQ:          566129673
detlef.bosau at web.de                     http://www.detlef-bosau.de