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Date: Thu, 2 Dec 2004 17:20:12 -0600 (CST)
From: Mike Silbersack <silby@silby.com>
To: Andre Oppermann <andre@freebsd.org>
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On Mon, 29 Nov 2004, Andre Oppermann wrote:

> If you have many TCP connections to one target it may happen that you
> get the same source port on the originator again within the TIME_WAIT
> timeout.  And if the ISN wrapped in the meantime the new connection
> will 'hang'.

Just to clear this up, the problem with randomized source ports and 
TIME_WAIT is not that the ISN is wrapping.  The problem is that if a port 
is reused too quickly, the ISN has not incremented enough and is less than 
the final sequence number of the previous connection.

There's code in 5.3 which eliminates this problem by incrementing a global 
offset for each connection established, I will probably MFC it before 4.11 
so that this problem is over with once and for all.

Mike "Silby" Silbersack