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From: jbvb@VAX.FTP.COM (James Van Bokkelen)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: What happens when TCP sequence numbers wrap.
Message-ID: <8910131706.AA10415@vax.ftp.com>
Date: 13 Oct 89 17:06:01 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 13

If your developer has been careful to test for the cases, and does the
compares right, everything works fine across both 0x7FFFFFFF ->
0x80000000 and 0xFFFFFFFF -> 0x00000000.  I've never seen Berkeley or
Sun TCP source code, but I know for sure that a Sun 386i running SunOS
4.0.1 does not handle the second case right.  I know for sure that our
TCP does.  The wrap case does matter, just leave a system monitor
running on a telnet or X connection for a while (depends on what
initial sequence number you get at open timethe fiorst time I tried it
took a weekend) and use a LAN monitor to watch the Sun ignore acks
after the boundary is reached...

James B. VanBokkelen		26 Princess St., Wakefield, MA  01880
FTP Software Inc.		voice: (617) 246-0900  fax: (617) 246-0901