Enabling the Windows XP Personal Firewall Feature on your Home Computer
Windows XP comes with a personal firewall that is very easy to use. You should take advantage of this feature to protect your computer from attacks. The XP Personal Firewall allows you to connect to the Internet while preventing the Internet from connecting to you. By using it, you ensure that the only Internet communications your computer is involved with are ones that your computer initiated.
To Install the XP Personal Firewall:
- Click Start
- Click Settings
- Click Control Panel
- Select Network Connections
- Select the connection that you use to connect to the Internet
- Right-click the connection icon and select Properties from the pop-up menu.
- On the Connection Properties window, click on the Advanced Tab
- Under the Internet Connection Firewall section, check the Protect my computer box

Note: Steps 9 through 19 are required to use Sidecar or CUWebAuth to access kerberized Cornell network resources.
- Click on Settings.

- Click on Add
- Create a new service called CIT Modified Kerberos
- In the next box down, enter 255.255.255.255
- In the next box down, enter 913
- Make sure it is set to TCP
- It should look like this:

- Click OK to close the Service Settings window
- Click OK to close the Advanced Settings window
- Click OK to close the Network Connection Properties window
- You should now see a small lock on the icon for the network connection - this indicates that the firewall is enabled on that connection.
Disabling the XP Personal Firewall
If you ever need to disable the XP Personal Firewall, just un-check the Protect my Computer box mentioned in the instructions above.