Protect your network

When you create a home network connected to the Internet, you increase the vulnerability of your computers to unauthorized access, including viruses. To protect your network, you need to create a type of barrier called a firewall. Windows XP comes with a firewall that you create when setting up a home network.

How does a firewall work?

Like an actual firewall built to prevent fire from spreading between adjoining buildings, computer firewalls prevent the spread of unauthorized communication between an individual computer or group of networked computers and the Internet. One of the most effective ways to protect a home network—and the least expensive—is to create a firewall on the ICS host computer, and to make sure that computer is the only one on the network with a direct connection to the Internet.

Other network possibilities

Another way to protect a home network is to use a hardware device called a residential gateway, or router. A residential gateway contains a firewall and replaces an ICS host computer as the central Internet connection. Because it contains no files, folders or other data, and cannot be used to manipulate computers to which it is linked, a residential gateway offers a greater degree of protection than an ICS host computer. Should a hacker manage to bypass the firewall, the only access gained is to the device, which is in effect empty. A disadvantage of a residential gateway is the extra cost it adds to putting together a network. You can create a home network having neither an ICS host computer nor a residential gateway, but at a high cost to security—and convenience. With such a setup, Internet access can be obtained by linking each computer directly to the Internet service provider via the computer's own modem, or else all computers on the network can be linked to an Ethernet hub, which functions as a central Internet connection. Neither of these methods provides firewall protection; and while Internet Connection Firewall can be enabled on networked computers running Windows XP, doing so prevents those computers from sharing files and devices such as printers.