Chapter 8. WI-FI NETWORKS

Wi-Fi (short for Wireless Fidelity, pronounced "why-fie") networks use radio signals instead of Ethernet cables to connect computers and other devices to a LAN. Wi-Fi is a convenient alternative to conventional wired networks because any wireless-enabled computer within range of the Wi-Fi signal can join the network; there's no need to find a network outlet. This can be particularly useful when it's not practical to pull data cables through walls, ceilings, and floors, and when a user wants to connect a laptop computer or a handheld device such as an iPhone or BlackBerry to an existing network or through a LAN to the Internet. And of course, thousands of Wi-Fi hotspots in public spaces such as airports, coffee shops, libraries, and schools offer easy access to the Internet when you're away from your own home or office.

However, Wi-Fi connections are far less secure than wired networks, because the same data that moves between a computer and a base station by radio can be intercepted by another computer. Even if the data is encrypted, a dedicated intruder with enough time can steal passwords, credit card numbers, and other personal information. However, the latest security tools, including WPA encryption and virtual private networks (VPNs), can go a long way toward making a Wi-Fi network secure.