Lab 15.4: Configuring Firewalls in Windows XP

Firewalls provide a security blanket that prevents others from accessing your computer from the Internet. Since the advent of permanent connections to the Internet like DSL and cable modems, you need a security system that provides full-time protection. Windows XP Professional includes a personal firewall system to provide this full-time security; it is called the Internet Connection Firewall.

A firewall works by making a forward/filter decision for every IP packet that comes to the interface. The decision is based on the source or destination IP address and on the TCP or UDP port that is being used. You should use the firewall to close down any unused ports or to exclude access based on IP addresses.

Upon completion of this lab, you will be able to enable the Internet Connection Firewall.

Set Up

For this lab, you will need a computer running Windows XP.

Exercise

If you are using DSL or a cable modem, you need to know how to enable the protection of the Internet Connection Firewall provided by Microsoft. This exercise will show you how to enable it to protect your computer and data from outsiders.

1. Open the Network Connections window:

   Start Connect To Show All Connections

2. Right-click on the icon to for your Internet connection. Select Properties from the menu to open the Properties window.

3. Click on the Advanced tab. Check the Protect My Computer and Network by Limiting or Preventing Access to This Computer from the Internet option in the Internet Connection Firewall section.

4. Click OK to close the windows and complete the activation of the firewall.