Editing Port scanner (section)

===Window scanning===
Rarely used because of its outdated nature, window scanning is fairly untrustworthy in determining whether a port is opened or closed. It generates the same packet as an ACK scan, but checks whether the window field of the packet has been modified. When the packet reaches its destination, a design flaw attempts to create a window size for the packet if the port is open, flagging the window field of the packet with 1's before it returns to the sender. Using this scanning technique with systems that no longer support this implementation returns 0's for the window field, labeling open ports as closed.<ref name=profmesser2>{{cite book |last1= Messer  |first1= James |title=Secrets of Network Cartography: A Comprehensive Guide to Nmap |url=http://www.networkuptime.com/nmap/page3-13.shtml |archive-url=https://web.archive.org/web/20060201065451/http://www.networkuptime.com/nmap/page3-13.shtml|archive-date=2006-02-01|access-date=2011-12-05 |edition=2nd |year=2007 |url-status= dead  }}
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