Firewalls

In simplest terms, a computer firewall functions to prevent unwanted communication between computers on the internet.  Think of them as security devices designed to keep others from taking control of your computer and using it to send junk mail, or from rummaging through the information stored in your computer, information such as your internet banking details, your credit card number, etc. 

Accordingly, IT Security at ANU highly recommends that you use a firewall with your personal PC or laptop.  Windows XP and Mac OS X both come with built in firewalls; all you need to do is turn them on.  In addition, ZoneAlarm is a free Windows firewall from http://www.zonelabs.com/. It is a little difficult to configure, but allows you to specify which programs are allowed to access the internet and which ones are not.  More information about personal firewalls can be found at http://security.anu.edu.au/firewalls/personal-firewalls.html.