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Date: Sat, 18 Oct 2003 14:46:55 -0400 (EDT)
From: Carl Mascott <cmascott@att.net>
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To: barney@databus.com
In-Reply-To: <20031018021648.GA26182@pit.databus.com>
cc: freebsd-net@freebsd.org
Subject: Re: TCP window size issues
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Ahhh, that may explain why, during FTP receive of a large file
over a 5 KB/s link with a 56 KB recv window, I get one or two
dropped packets at the same point every time, and then no
further dropped packets for the rest of the transfer.

Barney Wolff wrote:
> On Fri, Oct 17, 2003 at 08:16:32PM -0400, Carl Mascott wrote:
> > 
> > NOTE: AFAIK, 4.4BSD through FreeBSD 4.6-R seem to have done
> > alright without the PR 11966 patch, but if someone knows
> > different, please speak up.
>
> I'm not really surprised.  I would have thought that a well-behaved
> sender would be using congestion avoidance and limiting its transmit
> window so that packet drops should be rare, even with an oversize
> advertised window.  What's surprising is that this sort of tweak is
> ever required, other than as a minor optimization.