Firewall's, part three.

So know we know what they do, and why we need them.

What types of firewall are there?

They fall into two types, software firewall's and hardware firewall's.

If your running Windows XP SP2 their is a firewall built in and running.

Crazy and all as this might sound, it's only with the arrival of SP2 ( service pack 2) that Microsoft woke up and decided to actually turn on the firewall by default!

Previously you had to do this yourself, this is crazy and pretty indicative of the attitude at Microsoft, "give us your money, now feck off!"

In Mac OSX it's on by default, in Linux it's on by default and it will scream at you if you opt to turn it off! And rightly so....

The built in firewall in XP, OSX and Linux is quite effective and functional.

If their was any concern it's that they block traffic which is inbound ( as discussed earlier) but don't monitor outbound traffic.

What if something get's into our system ? It's on the "inside" so the firewall will allow it communicate to the outside world

A more sophisticated firewall will monitor ALL traffic , both inbound and outbound.

So an application which is on your computer on trying to connect to the internet will cause the firewall to ask the question "is this legit traffic", it will alert you and ask for your opinion!

It will "learn" from your response's what is legit and only ask when it sees something which it's thinks is suspect.

The other type is a hardware firewall.

If your on a broadband / ADSL connection then you have a hardware firewall, it's your modem!

The modem acts as a hardware firewall.

Most modems have a configuration file for the firewall which you can edit to do what you require. Of course most people don't even change the password for the modem, let alone configure it!!

In addition there are many dedicated hardware firewall's which you can place between your computer and your modem.

There is a very easy test which you can do right now to see if your computer is "talking to strangers" if you get a "true stealth" result then woohoo for you.

If you fail, you got some work to do, hop to it right away, like NOW :-)

I am going to send you on over to GRC.com ( Gibson Research Corporation ) take the simple test and with luck your good to go!

Check it out here .

Good luck :-)

Part four on the way!!!

  Firewall's -  Part 1 | Part 2|   Part 3 |