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Date:      Wed, 12 Jan 2005 17:07:36 -0800
From:      Julian Elischer <julian@elischer.org>
To:        net@freebsd.org
Subject:   TCP out-of-order packets.
Message-ID:  <41E5C9D8.4090209@elischer.org>

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I have a link which is provided by someone else that is 7 x E1s aggregated.
At leat it looks that way to me when I get to see it. however I have 
only been able to get
60kB.sec across this, despite having a tcp window size of 131072 bytes..
After investigation it appears that the link is massively re-orderring 
packets.
groups of upto 10 packets may appear in random order. (Maybe more, bu tI 
have seen 10)

in fact packets are rarely IN order.

This plays havoc with the tcp sessions.

I was thinking of writing a hacked up version of NATD that
instead of doing NAT, just did a pre-sort on packets from each session, 
so that the receiver would
see a stream of IN-order packets, with occasional delays.

firstly, does anyone have any tools to do this already (why build when 
you can borrow)
and secondly, does anyone have any experience with this sort of problem?

I have no control over or access to the link.. all I have is a promise 
that they will deliver
14Mb/Sec. with approc 300mSec. RTT to me but there is no promise about 
packet order.

I just get a 100Mb ethernet cable.





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