Software I've found that I think is particularly useful or interesting.

Use any software mentioned here at your own risk.

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2/5/2005: ZoneAlarm [>> Go]

    ZoneAlarm, or a program like it, is something that everybody should have installed on their computer. ZoneAlarm is a "personal firewall" - software that sits on your computer and monitors (and blocks) your network traffic. A "firewall", in computer terms, is hardware or software which can limit network traffic to or from a computer. When a computer is hooked up to a network, especially the Internet, it is possible for other computers to attempt to access it by sending specific requests that a program on the computer will respond to. Much of the time these requests are for a good reason - your computer sending information to a networked printer, or requesting a Web page from a far-off computer. But there exist a great number of ways for malicious people and programs to exploit this behavior, and problems with the software you may have installed, to cause unwanted results. Some computer viruses spread using this technique; computer hackers also can use this to gain access to your computer. Keeping up with the latest security updates from Microsoft and other software companies can go a long way to fixing the problems that can allow this kind of access, but software is so complex that it's unlikely to fix all the holes. Firewall hardware and software works at a deeper level than individual programs, and controls the actual network traffic that comes into or goes out of your computer. This makes firewalls an integral part of securing your computer (in addition to making sure you have all appropriate software updates for every piece of software you own). Personal firewall software, like ZoneAlarm, can also help you keep tabs on software on your computer that may be trying to use your Internet connection, and help you identify and block spyware and other malicious programs that you don't want to communicate with the outside world.

    One way to assess the vulnerability of your computer is to use an online service like ShieldsUp! that will remotely scan your computer over the Internet much like a hacker or worm/virus might do. What ShieldsUp does is attempts to talk to your computer on the many "ports" that programs on your computer, with or without your knowledge, may be responding to. Anything that ShieldsUp finds open could potentially be an access point for hackers or viruses/worms. You can close these holes by turning off the program on your computer that communicates via that port (for example, turning off the personal Web server in Windows), if you can find it, or by using a hardware or software firewall like ZoneAlarm. Personal firewall software allows you to block specific ports in your computer so that they are no longer vulnerable from the outside. The default settings in ZoneAlarm block most everything coming in to your computer, which gives pretty good protection from the outside world, but may interfere with services like peer-to-peer networks or personal Web servers. Only the Pro (non-free) version of ZoneAlarm gives you control over individual ports, which may be necessary for certain applications (or you can temporarily turn off ZoneAlarm while you use an application that it blocks). If you've got a home computer hooked up to a broadband (cable or DSL) connection, you absolutely must have either a hardware or software firewall. ZoneAlarm pops up warnings whenever a remote computer tries to talk to yours using a blocked port, which gets tiring after a while (broadband-connected computers are almost constantly being scanned); fortunately, you can check the "Do not show this again" box when a warning pops up and that particular warning won't show up again. It really doesn't matter how often your computer is being scanned; what's important is that ZoneAlarm is blocking it.

    ZoneAlarm's other beneficial security feature is that once ZoneAlarm is installed, any program on your computer that tries to access the Internet will pop up a warning like the picture above. You can click the "Allow" button if you want the program (like your Web browser) to access the Internet, or click "Deny" if you don't want it to. (If you don't want to be asked every time for the same program, check the "Remember this setting" box.) Once you install ZoneAlarm, you'll probably be surprised to find out how many programs try to use the Internet without your knowledge - Adobe Acrobat, WinAmp, Microsoft's Windows Media Player, etc. Many of these programs are checking to see if there are updates available, so that they can pop up a message to you asking if you want to download it, which is harmless. What you want to be on the lookout for are programs that you don't recognize, because these could be "spyware" or "adware" programs that are sending information about your computer (or even what you type on your keyboard, like passwords and credit card numbers) to advertisers or hackers or who-knows-who. When you see a warning about a program trying to access the Internet, if you don't recognize the name of the program try hitting "Deny" and seeing what happens. If a program you're trying to use won't work, or gives error messages, then run it again and this time click "Allow". You can always go into ZoneAlarm's configuration and change a program's access later on if you need to.

    While many high-speed Internet services include some hardware firewall protection (in your cable modem/router, for example), having a software firewall like ZoneAlarm installed gives you extra protection, not only from incoming threats but also to alert you to what on your computer might be using the Internet that shouldn't. I like ZoneAlarm's interface and features, and it's been completely stable on my PC (though it won't run on my wife's Windows ME computer) for years. If you need very specific network/port control, you'll have to upgrade to the Pro version, but I have only found a couple of applications that I couldn't get to work with ZoneAlarm running. It is by no means a cure-all for stopping spyware, viruses, and hackers, but it is one level of protection that you shouldn't be without.

©2019 Tyler Chambers