Perhaps the most important thing anyone wants out of a home network today is to share the single connection to the Internet that most homes have. Anyone with a decent broadband (cable modem or DSL) Internet connection that's always on knows how great it can be. In addition to being a lot faster than a modem, there's no need to dial up every time you start up your browser. It's even better when you can share that connection with every computer in the house, which requires a network.

To enable two or more computers to share the same modem, cable modem, or DSL connection at the same time, you need special software. If you have Windows 98 Second Edition or Windows Me, you can use the built-in Internet Connection Sharing. If you have a different operating system, you'll need to use proxy server software, such as WinProxy for Windows ($59.95; 888-946-7769) or Vicomsoft Internet Gateway for Macs. A proxy server sits between your computer and the Internet and acts as an intermediary. This software runs on the computer actually connected to the Internet -- usually called the gateway computer. Other computers access the Internet through their network links to the gateway computer. The sharing software acts like a traffic cop by making sure that the Web page requested by one computer gets routed to that computer.

Products dedicated to serving as your home network's Internet gateway are also on the market. With a dedicated gateway helping you share an Internet connection, you don't have to devote a computer to the task -- after all, it takes work for a gateway computer to administer to the Internet connection needs of other PCs on the network. Some gateway products mix the traditional wired and wireless world, such as 3Com's Home Wireless Gateway ($399; 800-638-3266). This product is compatible with Wi-Fi adapters, and also lets you plug in three Ethernet-connected computers on a network.

If you use America Online (AOL) as your primary Internet service provider (ISP), you may have some restrictions when using Internet sharing software. In many cases only the gateway system can access the AOL service -- other computers on the network can browse the Web but can't access AOL.

While convenient, an always-on broadband connection can make your computer vulnerable to hacking. You should run firewall software such as ZoneAlarm for Windows (free) or Norton Personal Firewall ($49.95 for Windows, $69.95 for Mac; 877-255-7907) on the computer that is connected to the Internet.

An alternative to a software firewall is a separate hardware Internet gateway with a firewall built in. The 3Com Home Wireless Gateway has one, as does the SOHOware Broadband Internet Gateway ($130; 800-632-1118). Both provide firewall protection for an Ethernet or 802.11b/Wi-Fi network.