[56629] in North American Network Operators' Group

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Re: 923Mbits/s across the ocean

daemon@ATHENA.MIT.EDU (Stephen Sprunk)
Tue Mar 11 13:35:55 2003

From: "Stephen Sprunk" <stephen@sprunk.org>
To: "Iljitsch van Beijnum" <iljitsch@muada.com>,
	"Richard A Steenbergen" <ras@e-gerbil.net>
Cc: "North American Noise and Off-topic Gripes" <nanog@merit.edu>
Date: Tue, 11 Mar 2003 12:18:35 -0600
Errors-To: owner-nanog-outgoing@merit.edu


Thus spake "Iljitsch van Beijnum" <iljitsch@muada.com>
> This is the part about TCP that I've never understood: why does it
> send large numbers of packets back-to-back? This is almost never a
> good idea.

Because until you congest the network to the point of dropping packets, a
host has no idea how much bw is actually available.  Exponential rate
growith finds this value very quickly.

> Hm, I don't see this happening to a usable degree as TCP has no
> concept of records. You really want to use fixed size chunks of
> information here rather than pretending everything's a stream.

A record-oriented, reliable transport would make many protocols much easier
to implement.  Too bad SCTP hasn't seen wider use.

S

Stephen Sprunk         "God does not play dice."  --Albert Einstein
CCIE #3723         "God is an inveterate gambler, and He throws the
K5SSS        dice at every possible opportunity." --Stephen Hawking


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