This article describes how to share one Point to Point Protocol over Ethernet (PPPoE) Internet connection on your home network or your small-office network.

Back to the top

You can use the Windows XP Internet Connection Sharing (ICS) feature for network and dial-up connections to connect your home network or your small-office network to the Internet. For example, you may have a home network in which a Windows XP-based computer connects to the Internet by using a PPPoE broadband connection. If you enable ICS on the computer that uses the PPPoE connection, you can provide network address translation (NAT), addressing, and name resolution services for all of the computers on your network.

Note that for ICS to be enabled, the Windows XP-based computer must have two network adapters, one for the home or small-office network, and one for the Internet connection.

This article assumes that the PPPoE connection is set up, and that the intended ICS host can successfully connect to the Internet.

For additional information about how to create a PPPoE connection in Windows XP, click the article number below to view the article in the Microsoft Knowledge Base:

Back to the top

To Enable ICS on a PPPoE Broadband Network Connection

1.	In Control Panel, double-click Network Connections.
2.	Click the PPPoE connection under the Broadband group that you want to share, and then click Change settings of this connection under Network Tasks.
3.	On the Advanced tab, click to select the Allow other network users to connect through this computer's Internet connection check box.
4.	PPPoE connections behave in a similar way as do dial-up networking (DUN) connections, and you may want the connection to be automatically dialed when another computer on your network attempts to connect to the Internet. To do this, click to select the Establish a dial-up connection whenever a computer on my network attempts to access the Internet check box.
5.	If you want to allow other network users to enable or disable the shared Internet connection, click to select the Allow other network users to control or disable the shared Internet connection check box.
6.	Under Internet Connection Sharing, in Home networking connection, click the LAN (Local Area Network) connection that connects the computer that is sharing its PPPoE Internet connection to the other computers on your network. NOTE: When you select the connection to share, it must be the external connection that connects the ICS host to the Internet. Selecting the wrong connection causes ICS to not work.

NOTE: To enable ICS in Windows XP, you must have administrative permissions.

IMPORTANT: When you enable ICS, the network adapter that is connected to the home or small-office network receives a new static IP address of 192.168.0.1, with a subnet mask of 255.255.255.0. Existing TCP/IP connections on the network may be lost, and if this occurs, you must re-establish them.

Back to the top

Configuration and Usage Issues

The ICS feature is intended for use in a small office or in a home office in which the network configuration and the Internet connection are managed by the Windows XP-based computer on which the shared connection resides. It is assumed that on this network, this computer is the only Internet connection, this computer is the only gateway to the Internet, and this computer sets up all internal network addresses. All hosts on the network except the ICS host are expected to be configured to obtain IP address and DNS configuration automatically.

You cannot modify the default network configuration after you enable ICS. This includes changing the range of private IP addresses that are handed out (DHCP allocator), enabling or disabling DNS, and configuring a range of public IP addresses.

If your home office users need to gain access to a corporate network that is connected to the Internet by a tunnel server, the users need to create a virtual private network (VPN) connection to tunnel from the computer on the ICS network to the corporate tunnel server on the Internet. The VPN connection is authenticated and secure, and creating the tunneled connection allocates proper IP addresses, DNS server addresses, and WINS server addresses for the corporate network.

You may need to configure programs and services to work properly across the Internet. For example, if users on your home network want to play a game with other users on the Internet, the game must be configured on the connection in which ICS is enabled. Services that you provide must be configured so that Internet users can gain access to them.

For additional information about related topics, click the article numbers below to view the articles in the Microsoft Knowledge Base:

Back to the top