Absolutely bloody vital, that’s what a firewall is.

It is a barrier between your computer and the Internet. A cast iron door that stays shut and keeps the bad guys out.

Like it or not, the Internet is alive with worms, hackers and other background radiation (a wonderful term Steve Gibson invented). Without some shutter, your computer could get infected in seconds.

In fact if you take a Windows 98 machine and plug it in to an unprotected Internet connection (no firewall) you can watch it get attacked and die within minutes!

A firewall works by blocking any Internet traffic from coming in, unless it was specifically invited. So if you go to a web site, the firewall will allow the pages to download. But if a worm tries to enter, it will be denied access.

Firewalls come in two flavours; hardware and software. The hardware ones are the best. This means it is a physical device, usually built in to your Internet modem, or it could be stand alone. The software sort is just a program running on your computer. Windows XP has one built in. It is basic but it works.

I find Zone Alarm and all other add-on software firewalls to be bad for most users. Avoid.

A software firewall running on your computer can be fooled or shut down by other software. They also have an annoying habit of popping up every few seconds and asking you if you want to allow this or deny that - blah blah blah. People tend to go into auto-pilot and just press anything, making the firewall useless.

There is also a third sort which is software running on a separate dedicated computer. This is still technically a hardware firewall because the whole thing is a separate box, just because it’s a PC acting as a firewall device doesn’t make it any less effective. If a PC is dedicated to the job of firewall, then it’s a hardware firewall. There are some great FREE options in this class that work well. Most use Linux as it is open source and free. If you have an old PC that you can dedicate, this might be an option for the advanced user. Try the Astaro Security Gateway.

A hardware firewall can not be shut down by software (unless you have a weak password on your modem) and is much more effective. They don’t ask questions, they typically just work properly.

If you have an Internet modem without a firewall, unplug it immediately! Well, read the rest of this article first and then unplug it... The blue Telstra stingray shaped modem (yeah, it’s actually shaped like a stingray fish) and the black Telstra Speed Touch Home (but the Speed Touch Pro is Ok) are classic invitations to infection and should NOT be used.

Really Dangerous!!!!

A modem with a firewall built in is dirt cheap. You can get a Linksys, D-Link or Netgear (3 brands I like) at your local electronics shop for less than a hundred Aussie dollars. Avoid the no-brand junk. I don’t like Asus, Billion, Netcomm or anything without a brand on it.

Linksys is popular with me as they are owned by Cisco who make serious networking stuff.

Pretty Blue!