McAfee Personal Firewall and Zone Alarm are suitable for the personal computer. This type of firewall is called a Dual Host Gateway. It filters all communications, is user friendly, and lets you know when someone is trying to gain unauthorized access to your computer. For network systems, there are two basic types of firewalls. The first is a Demilitarized Zone Firewall that puts a buffer zone between the internet and a computer.
All information passes through the buffer zone.
This usually has a computer between the protected computer and the internet and is most suited for the small business. This filters every communication. For a comparative listing of intrusion detection software, see the June 2000 issue of SC Magazine . Take the Hacker Whacker test and see if your computer has an open back door. Remember to maintain the most current version of your anti-virus program and the latest security patches for your browser.