A free service called ShieldsUP! will quickly test the Internet connection on your Windows-based computer, determining whether it is fully secure or open to penetration. By clicking "Test My Shields" the ShieldsUP! server will attempt to connect to your computer's Hidden Internet Server that leaves your personal files exposed to anyone on the Internet. The evaluation will alert you to any vulnerabilities within your computer or praise you for how well your firewall is performing, while also offering suggestions for improvement.
Another free test, "Probe My Ports," attempts to establish standard TCP Internet connections with basic, and often susceptible, Internet service ports on your computer. Successful connections demonstrate which of your ports are open, closed, or in stealth mode from passing Internet port scanners. Testing is conducted on the ports that correspond to various services, such as FTP, Telnet, finger, HTTP, NetBIOS, and IMAP, among others.
Comprehensive and technical explanations, along with solutions, are outlined with the test results. The free evaluation services are part of a much larger site, Gibson Research Corporation, that includes highly technical content and resources regarding Internet security. The firm offers other protective applications UnPlug n' Pray, ID Serve, Wizmo, and LeakTest along with the data recovery program, SpinRite 5.0.