On Wed, Aug 02, 2006 at 01:55:12PM -0700, Darrin Chandler wrote:
> On Wed, Aug 02, 2006 at 04:28:41PM -0400, Thor Lancelot Simon wrote:
> > 
> > How do you know the data were not corrupted after the TCP checksum was
> > performed?
> 
> If that were the case then it would have been dropped and retransmitted.
> That's the whole reason for a TCP checksum.

Uh, no.  What you wrote above _would_ be true _if_ I'd written "after the
TCP checksum was performed by the source host" -- but I didn't.

Data corruption after the TCP checksum is validated on receive happens all
the time; there is a whole family of rather expensive gigabit Ethernet
controllers in which about every 3rd member has bugs that cause it to
corrupt data _after_ checking the TCP checksum!

Thor