*> From listadm(_at_)loki(_dot_)ietf(_dot_)org Fri Apr 5 11:50:30 2002
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*> Date: Fri, 05 Apr 2002 14:29:44 -0500
*> From: Rob Austein <sra+ietf(_at_)hactrn(_dot_)net>
*> To: ietf(_at_)ietf(_dot_)org
*> Subject: Re: TCP Checksum Interoperability
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*> The last time this came up for a TCP implementation I used to
*> maintain, our interpretation of Robustness Principle applied to this
*> problem dictated that we shouldn't send segments with checksum fields
*> set to all ones (that is, we shouldn't send ~(+0)), but that we had to
*> accept either ~(+0) or ~(-0) in received segments.
*>
*> Strictly speaking, either zero state is completely legal, but one is
*> (apparently) more surprising to most implementors than the other, due
*> to the implementation techniques that suggest themselves on most
*> modern processors.
*>
We thought we had laid these issues to rest in 1988, in RFC 1071.
Bob Braden