After you have a network set up, you should check to see which protocols are installed on the computers. Unnecessary protocols should be removed as they can slow down the network communication and in some cases pose as a security threat.
TCP/IP is the default network protocol installed in Windows XP. As long as all the computers on your network are running the same protocol, you can remove the protocols not being used. You can do so by opening the Network Connections applet within the Control Panel. Right click your local area connection, highlight the unwanted protocol, and click the Uninstall process. Conversely, you can use the Install button to add additional protocols.