InformationWeek SMB TechEncyclopedia

(wireless Local Area Network) A communications network that provides connectivity to wireless devices within a limited geographic area. "Wi-Fi" is the universal standard for wireless networks and is the wireless equivalent of wired Ethernet networks. In the office, Wi-Fi networks are adjuncts to the wired networks. At home, a Wi-Fi network can serve as the only network since all laptops and many printers come with Wi-Fi built in, and it can be added to desktop computers.

     Wi-Fi LANs do not require line of sight between sender and receiver. Wireless base stations, called "access points," have antennas that transmit and receive a radio frequency within a range of 30 to 150 feet through walls and other non-metal barriers.

Machines Can Be Retrofitted
Old laptops can be upgraded with Wi-Fi adapters via a PC Card slot or USB, and desktop computers in distant rooms can be made wireless by plugging a wireless adapter into a USB port.

The Wireless Router - All In One
A wireless router is the foundation network component in most homes and small offices, combining wired and wireless in one unit. It is an access point, switch and router. The access point is the wireless base station, the switch interconnects four wired and any number of wireless devices, and the router forwards Internet traffic to the modem, which is attached to the cable company's coaxial cable or the telephone company's DSL phone line.

     Since all wireless and wired computers are interconnected, they can exchange data with each other for backup and file sharing. For technical details of the wireless standards, see 802.11. See hotspot, router, LAN switch, wireless broadband and WPAN.




Wireless LAN
This shows wired and wireless networks working together. In a large office, access points, switches and routers are stand-alone products. An access point is like a cellphone tower, but its signal distance is measured in feet, not miles. In a large building, users can roam between access points without losing a connection.





Wireless Router
For small networks, a wireless router combines router, access point and switch. The antennas are the Wi-Fi, the 1-2-3-4 Ethernet ports are wired to computers and printers, and the Internet/WAN port is for the cable/DSL modem. This Belkin unit uses two antennas to send and three to receive (see MIMO). (Image courtesy of Belkin Corporation, www.belkin.com)