Protect Your PC For Free! No More Excuses!
by Michael Oliveri - Author's Homepage - Thursday, 27 March 2003.
Another component to system protection is the firewall. In simplest terms, a firewall protects your computer from unauthorized traffic, both inbound and outbound. Generally speaking, your computer should not be listening for requests. However, Trojan Horse programs, unauthorized spyware, and non-firewalled Windows File and Print Sharing can be announcing any number of things to the outside world, which means you can be giving away personal information or relinquishing control of your system without even knowing it! Mac OS X, Windows 2000 and XP, and Linux all have built-in firewall capabilities and I strongly recommend you learn to use them, especially if you have a broadband connection. They are not hard to configure. If you are using a broadband gateway or router to share your broadband connection to multiple PC's, you should have a firewall built into the unit. Some cable and DSL modems come with built-in firewalls as well. See your manufacturer's website or documentation for more information. An even easier method is to use a software firewall. ZoneAlarm from Zone Labs is a great option for Windows users. Not only does it provide good protection but it works on a program-by-program basis rather than having to deal with ports and protocols. When you first run Internet Explorer or your browser of choice, ZoneAlarm asks for permission which you can grant on a permanent or temporary basis. The beauty here is when a Trojan Horse runs on your system, ZoneAlarm will catch it, tell you what's running, and you can deny traffic until you can figure out what's happening. It also alerts you to altered programs, so if a virus infects an executable to piggyback on its traffic, you'll know about it.

Like AVG, ZoneAlarm comes in several flavors of paid versions, but again, it's all extra bells and whistles you may never need or use. The free version has been more than adequate for my home modem connection. You can also test its reliability (as well as that of any firewall) by running Steve Gibson's ShieldsUP!.

Finally, we come to Microsoft Outlook and Outlook Express. While Outlook and its variants are solid email clients with a lot of excellent features, let's face it: it has a very poor reputation that has led to several viruses being tagged "OTD's," or "Outlook-Transmitted Diseases," by the security community. It's intended as tongue-in-cheek humor, but unfortunately there's truth behind it. Unless you are consistently updating Outlook alongside Windows, chances are you're going to fall behind on patches and become vulnerable.

Fortunately there are several free mail clients out there. If you're running Mozilla, Opera, or Netscape as your browser of choice, you've already got email capability built in. Jump in and tinker, you may be surprised at what it can do. My personal favorite email client is Eudora, and I wish like hell they'd port it to Linux. Windows and Mac users can download it for free at Simple, powerful, and elegant. Great stuff.

With all this information available, there really is no excuse for becoming infected or spreading viruses other than plain user ignorance. My school's network receives several per week, and I am constantly emailing people to teach them how to prevent the spread of viruses. While no software will ever become 100% resistant to viruses, proper use and maintenance and user education can go a long way to stopping the spread of these malicious viruses.


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