Wireshark-users: [Wireshark-users] TCP connection window size change question

From: George Vandelet <george_vandelet@xxxxxxxxx>
Date: Fri, 23 Jul 2010 09:22:46 -0700 (PDT)
Wireshark superusers,
 
I have been looking at captures and many times I see at the end of an TCP HTTP session a TCP packet (or series of TCP packets) that looks to (in wireshark) change the window size.  Why does wireshark show that the window size changes right before the TCP session is closed?  It does not make sense to change the window size after the first FIN,ACK ->ACK exchange has been done as there is nothing to do after that except for close the connection with the following FIN,ACK ->ACK!
 
 
Thanks!
 
George