The Port Scan hosted on our website is temporarily offline.
In the mean time, Steve Gibson's "ShieldsUp" tool is a worthy program until we redesign and reconfigure our scanner.
The objective of the Port Scan is to see how secure your PC is from people who want to break into your machine. DSLreport's port scan originates from "monitor.dslreports.com" as stated on the port scan page. What it does is send various packets that look for open TCP and UDP ports. It will let you know if you have open, closed or filtered port(s).
Stop by the Security Forum if you fail on information on a firewall. (A firewall is a must have for broadband connected machines.)
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