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From: ron@BRL.ARPA (Ron Natalie)
Newsgroups: mod.protocols.tcp-ip
Subject: IP, ICMP, TCP, and UDP checksumming.
Message-ID: <8510230413.AA04085@UCB-VAX>
Date: Wed, 23-Oct-85 00:03:59 EDT
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Posted: Wed Oct 23 00:03:59 1985
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This has come up before, but I don't know if we came up with an answer.
When doing the complement of the ones complement sum, do you fix negative
zero to be zero; pick one: never, after the sum and before the complement,
after the complement.

The obvious solution is to never normalize the value you insert in the header
but always check for a comparison of 0 equals -0 when doing verification.  Or,
do we want to get more rigorous.

-Ron