Wireless Routers

Wireless routers, also known as wireless access points or base stations, are actually several networking devices at the same timethey comprise everything we've covered so far from the mechanism by which the computer is connected to the network (the wireless hub or switch) up to the routing mechanism for passing traffic up to the next router. Because they're generally inexpensive (less than $200), wireless routers don't give you the full capabilities of industrial-strength routers; rather, because most of these devices are designed to fit unobtrusively into a home or corporate network, they perform the minimum required duties of getting your computer's communications up to the next router on the way to the Internet (for example, a cable modem or a corporate LAN).

The IEEE 802.11 protocol is the wireless LAN communication standard. Two variants of this protocol are in wide use today: 802.11b (which transmits at 11Mbps) and 802.11g (which transmits at 54Mbps). 802.11g devices are favored today because of their greater speed and ability to support more simultaneous users than the older 802.11; however, all the computers on your wireless network have to support 802.11g, or else the network will revert to 802.11b as a lowest common denominator.

Note

802.11a is a variant protocol that supported 54Mbps communication at the same time that 802.11b was popular; but it did so by using a dedicated 5GHz radio frequency, rather than the 2.4GHz shared by devices such as microwaves and cordless phones. This higher frequency eliminated interference from those devices, but it also made it so that the wireless signal could be easily blocked by walls and had a much smaller overall range. 802.11g combines the speed of 802.11a with the range of 802.11b, the best of both worlds; but it means your wireless signal reception might suffer if you use a 2.4GHz cordless phone.

Because it doesn't depend on physical cables, a wireless network has an additional complicating factor beyond a wired one: security. The wireless router can be configured to require a password to allow a computer to join its network; it can also use encryption such as WEP (Wired Equivalent Privacy), or its stronger successors WPA (Wi-Fi Protected Access) or WPA2, to ensure that your wireless communications can't be decoded by an eavesdropper who might literally be hiding in your eaves with a laptop and a wireless card.

Many reputable companies make excellent wireless routers: D-Link, Netgear, Linksys, and Apple all have well-regarded and easy-to-use contenders. Some (like Apple's AirPort Express) even have additional features such as audio output, which lets them link into your stereo so you can beam music to it over the airwaves. Typical prices range from $100 to $200 or more, depending on the feature set; but if you're on a budget and adventurous, you can set up a FreeBSD machine as a wireless router, using the methods described in the "Configuring a Wireless Internet Access Point" section of Chapter 28.