Probe Your Ports: Shields UP!! is a free service of Gibson Research Corporation. It is a tool that you can use to probe your own computer to check for security vulnerabilities, namely open ports. Shields UP!! is trustworthy and discreet, and has been relied upon for more than 50 million scans since its inception.

New and Improved: If you are already familiar with Shields UP!!, but you haven’t checked it out lately, you may want to. Mr. Gibson keeps enhancing it, adding more and better tests to the suite. He has named to the current version the “Port Authority Edition.” Details of all the new features are listed at www.grc.com/np/pa-features.htm.
Simple to Use: You get to Shields UP!! through the Gibson Research website (www.grc.com/x/ne.dll?bh0bkyd2). First, click on the “Proceed” button. You will then be presented with a menu of Shields UP!! services: File Sharing, Common Ports, All Service Ports, Messenger Spam, and Browser Headers. Each one of these represents a different type of vulnerability. First time users should start by checking their Windows File Sharing and Common Ports vulnerabilities with the “File Sharing” and “Common Ports” buttons. Just click on the button for the service of choice, and the probe will begin immediately. The website automatically determines the IP address of your computer (because your browser tells it so). You don’t have to do a thing except wait for the probe to finish and then view the results. If both of those first two tests pass, then you can breathe a little easier.

Details, Details: The Shields UP!! site is loaded with detailed explanations, how-to’s, and other resources. Everything you need to know about these vulnerabilities, and what to do about them, is all right there.

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