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

At 10:17 AM -0400 9/1/14, Noel Chiappa wrote:
>     > From: Detlef Bosau <detlef.bosau at web.de>
>     > What is precisely the difference between flow control and congestion
>     > control?

That is in the spirit of what I have been using:

Flow control is where feedback is co-located with the resource being 

Congestion control is where feedback is not co-located with the 
resource being controlled.

Remove as many specifics about the implementation as possible.


>I think it would be hard to beat the definitions given in Davies' '72 paper:
>Flow control is about end-to-end control on individual 'connections' (in the
>generic sense of the term, i.e. not limited to a reliable stream); i.e. for
>the transmitter to make sure it does not send data faster than the ultimate
>consumer can deal with it.
>Congestion control is about too much traffic being offered to _the network_
>between them, and often involves the interaction of _multiple_ connections
>(although a single connection can cause network congestion on its own, if the
>ends can produce/consume data faster than the network between them can carry
>it across.
>	Noel