Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!cwjcc!hal!ncoast!sgtech!adnan
From: adnan@sgtech.UUCP (Adnan Yaqub)
Newsgroups: comp.protocols.tcp-ip
Subject: What happens when TCP sequence numbers wrap?
Message-ID: <ADNAN.89Oct12083745@sgtech.UUCP>
Date: 12 Oct 89 07:37:45 GMT
Sender: adnan@sgtech.UUCP
Distribution: na
Organization: Star Gate Technologies, Inc.
Lines: 14

I was looking over the Berkeley TCP code and began to wonder what
happens when TCP sequence numbers wrap.  In the tcp_input routine
duplicate acks are detected by the check (after macro expansion):
	(int) (segment ack - last unacknowledged) <= 0
It seems to me that if I send a message which ends at, say, sequence
number (2**32)-1, then when the ack arrives (which would be 0) I would
reject it as a duplicate.

Is this comething which is not worried about, or am I missing
something?
--
Adnan Yaqub
Star Gate Technologies, 29300 Aurora Rd., Solon, OH, USA, +1 216 349 1860
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