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Did you know that when you access the Internet, your computer could be vulnerable to an outside attack? And if you are using one of those speedier broadband services such as a cable modem or ADSL, you're even more accessible to evildoers looking for someone's computer to pilfer. Going online is in many ways synonymous to leaving the front door of your home wide open. Even worse, it's like leaving your door open and you live in a bad neighborhood.

When you log on to the Internet through an Internet service provider (ISP), your computer is assigned something called an IP address. In most cases you are assigned a different address each time you log on. When you're finished, the address goes back into a pool to be used again by another user for their session. This dynamic allocation helps to keep a provider's overhead costs down since it can serve more subscribers with a smaller number of those costly IP addresses. The theory is that most subscribers to an ISP don't all log on at the same time. Of course, as its subscriber base grows, the ISP needs to obtain a larger pool of addresses. If it doesn't, you might find it harder to log on during peak usage times. In some instances, it's desirable to have a fixed IP address and most ISPs offer this service at a higher cost. But having a fixed IP address actually makes you a bigger target to hackers because once they find you, you're always there.

Hackers use sophisticated software that checks through a range of IP addresses to see if anyone is using that address at a particular moment in time. Since cable and ADSL technologies use an "always on" protocol, hackers stand an even greater chance of finding you online than if you have a standard dialup modem connection. Ways to see if an IP address is in use varies but basically the method entails the hacker sending your computer a tiny bit of information and if that data is sent back (one of these methods is called "pinging"), the hacker knows you are online and operational. Once detected you could be in a lot of cyber-trouble.

A firewall is a piece of software the literally makes your computer invisible to pinging and other similar detection procedures. When a piece of data is sent to your IP address, the firewall software detects it and literally absorbs it rather than letting it bounce back. With no reflection, the hacker's software gets no acknowledgement and it just moves on to the next address for testing. Of course, this explanation is an oversimplification of a highly complex subject but it gets the basic idea across. Because of its complexity, firewall software has been the stuff of interest and implementation by network engineers. But now McAfee has come up with a firewall for the rest of us.

The McAfee Personal Firewall is a program that lets the average Internet surfer implement a sophisticated firewall on their own PC. Personal Firewall does this by taking the driver's approach to operating a car rather than a mechanic's approach. Personal Firewall doesn't bog its users down with all the technical jargon and cryptic data displays because McAfee understands that most of its users wouldn't understand all of that stuff anyway. Personal Firewall just gets the job done. Install it by answering a few simple questions and it makes your computer invisible to hackers, period. It's the network engineers who want all the technical data so they can find out who is hacking them and from where. McAfee's approach to Personal Firewall is that its users don't care about catching anyone. They just want to be safe from people trying to get into their computers. It's like having a really good lock on your door but no alarm system to call in law enforcement. The really good lock just keeps them out of your home and Personal Firewall just keeps them out of your computer. It adopts the philosophy of other security minded applications such as antivirus programs. Users don't want to find out who wrote the virus. They just want to keep their computers safe from infection.

McAfee's Personal Firewall should be available by the end of March and is for Windows based computers only. Pricing has not yet been set. For more information, check out McAfee's web site at: www.mcafee.com.