Norton Internet Security Is Symantec's Offering for a personal firewall. This product was originally AtGuard's, but Symantec took over the company and re-labelled the software as its own.

The program installs very easily, using Microsoft Window Installer (that used in Office 200). Once installed you can set up accounts for different users, say if you want your children not being able to send certain information across the 'net (such as your home address) you can enable this. You can used the many built-in templates, such as "teenager" and "supervisor". Or you can leave this feature alone if you don't want the hassle, or don't have children.

Like many personal firewalls, NIS works on a probgram-by-program basis. You can make each program ask for priveledges before it can communicate, or you can let NIS decide which applications you should let through. Me being a sceptic, I decide what can go through the firewall.

Yet, all this comes at a price, around £45 for your own copy, but they do offer a trial version at their website, so you can try it for a month before parting with your pennies.

The basic interface is simple and easy to set up. But the advanced features are harder to get to grips with, and there's the possibilty you could damage your Internet connecytion if you apply the wrong settings.

Another great feature (although many big companies will hate me for saying this) is the advert blocker. We've all seen those annoying adverts that take longer to download than the actual page itself. Well NIS looks for certain things in an image on a web page, for example if the image is stored in a folder called "ads" it will tell the browser not to download it, making i faster to surf. Although I have found this has restricted access to some sites, where the page appears blank.

I've mentioned the privacy feature briefly, basically what is does is it chec
ks what information is sent across the Internet, and prompts or disallows the information to be sent. You could use this to make sure your credit card details aren't sent out to dodgy websites etc. This program is excellent for worried parents since they can specify what sites, and programs can be used on the 'net and what information can be given out.

Where NIS really shines is how you can control which ports each application has access to. This is really for the more technical, and the extremely weary. For example, your browser only needs access to a few ports to work, so any other ports aren't needed and can be blocked. Also NIS can try to work out how to configure itself to each application by its in-built library of program definitions.

All in all, a great product, albeit a little difficult to set up. It's a shame about the price tag when there are cheaper alternatives (such as the free Zone Alarm) around.