Internet Connection Sharing in Windows XP
This article explains in detail how to set up a small network at home so you can
share your Internet connection between two computers running Windows XP.
Sharing the Internet connection between two computers running Windows XP
Connect the first one of your computers (the server) to the Internet and test
the connection to make sure that it is working properly. Then click Start >
Control Panel > double click Network Connections > right click the
Internet connection and select Properties. Click the Advanced tab and check the
Allow other network users to connect trough this computer's Internet connection.
Leave the option Allow other users to control or disable the shared Internet
connection unchecked or checked depending on your preferences. Click OK.
In order to share your Internet connection you need to network your main
computer (the server) with your other computer (the client) - this can be done
with cross-over cable connecting the two PCs' network cards.