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

Regarding algorithmic solutions:

Detlef Bosau wrote (in different messages):

Also, in reference to earlier comment re.:
> There are dozens of all days life examples where resources must be
> allocated or assigned, we have well proven algorithms for these
> purposes. E.g. in Germany, you can travel by car from Flensburg to
> F?ssen. And there is no need for probing, no need for dropped cars and
> car corruption is considered an accident./ 

Not only is this not the case, the situation is simply different: Cars 
are self-driving, with drivers making moment to moment decisions as to 
their routing, potentially with input as to global traffic conditions -- 
last time I looked, packets can't do that (though, admittedly, routers 
are doing that for them, as they make next-hop decisions based on the 
state of routing tables).

It's an engineering decision as to which is more effective and efficient 
- dropping packets in the face of congestion, with end-to-end 
retransmission, or buffering them in the switches (store-and-forward).  
An awful lot of experimentation and real-world practice suggests that 
dropping packets is a lot simpler, and uses fewer resources, than a 
store-and-forward or connection oriented approach.  The equation changes 
under conditions of high-delay links, network disruption, and such - 
hence the use of store-and-forward in some of the protocols being 
developed for delay/disruption-tolerant networks - particularly where 
inter-planetary distances and delays are a serious consideration.

> 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.)

Ummm.... you're missing all the stuff going on behind the scenes, in the 
form of routing protocols.  Packets are not sent off willy nilly in all 
directions - they're sent in the directions indicated by routing tables 
that are updated based on, among other things, resource congestion 
around the net.

In theory, there is no difference between theory and practice.
In practice, there is.   .... Yogi Berra