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

    > From: Detlef Bosau <detlef.bosau at web.de>

    > What is precisely the difference between flow control and congestion
    > control?

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.