From owner-freebsd-hackers  Wed May 30 19: 5:47 2001
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To: Brooks Davis <brooks@one-eyed-alien.net>
Cc: Bob Willcox <bob@immure.com>,
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From: "Louis A. Mamakos" <louie@TransSys.COM>
Subject: Re: How to disable software TCP checksumming? 
References: <20010529144114.I19771@luke.immure.com> <20010529221107.C49875@skriver.dk> <20010529155212.M19771@luke.immure.com> <20010530045200.A1031@hades.hell.gr> <20010529235215.A60177@luke.immure.com> <20010530085155.B24096@Odin.AC.HMC.Edu> 
In-reply-to: Your message of "Wed, 30 May 2001 08:51:55 PDT."
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The TCP checksum protects more than just the contents of the packet
on the wire; it's also a (somewhat) weak check on the contents
of your packet sitting in memory, and as it's going over the bus
in your computer between memory and peripherals and for other end-to-end
sorts of issues. 

Of course, with rude things like NAT boxes and other network elements
taking liberties with your data, this becomes less and less useful
as time goes on, sigh.

louie


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