You can use Internet Connection Sharing (ICS) to share an Internet connection among two or more computers on a network. First, you need one computer, called the host computer, that is connected to the Internet and that has a separate connection to the other computers on your network. You enable ICS on the Internet connection. The other computers on your network then connect to the host computer, and from there to the Internet through the host computer's shared Internet connection.
If your computer is connected to a network, network policy settings might prevent you from completing these steps.
On the host computer (the computer whose Internet connection you plan to share):
Open Network Connections by clicking the Start button , clicking Control Panel, clicking Network and Internet, clicking Network and Sharing Center, and then clicking Manage network connections.
Right-click the connection that you want to share, and then click Properties.
If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
Click the Sharing tab, and then select the Allow other network users to connect through this computer’s Internet connection check box.
The Sharing tab will not be available if you have only one network connection.
Now you need to make some changes to the other computers on the network. For more information, see Change Internet settings for ICS (Internet Connection Sharing).