Public and private network connections

In a home or small office network that has Internet Connection Sharing (ICS) enabled, there are two network connections, one public and one private.

The public network connection is the connection to the Internet. Any type of modem—28.8 or 56 kilobits per second (Kbps), ISDN, DSL, or cable modem—that is connected to the computer can provide and direct network communication to and from the Internet to all the computers on your network. The modem acts as a network adapter.

The private network connections are those that connect the computers together as shown in this illustration. The computers on the network communicate with each other and send Internet requests through the network to the computer with a residential gateway device (or to the ICS host computer).

This connection method can help provide an enhanced degree of security for your home or small office network. Files and folders that are shared on any computer are protected and will not be seen by anyone on the Internet.

Before installing the second network adapter on your ICS host computer, we recommend that you rename the modem or network connection that is connected to the Internet. This is so you can easily identify the connection to the Internet.

Notes

In Microsoft Windows XP Service Pack 2 (SP2), Windows Firewall is turned on by default for all connections, both public and private.
Most external DSL and cable modems are connected to an Ethernet network adapter. Check the manufacturer's specifications to determine the type of network adapter required to connect to your external DSL or cable modem.