Overview

A wireless local area network (WLAN) is a flexible data communications system implemented as an extension to, or as an alternative for, a wired LAN. WLANs transmit and receive data over the air via RF technology, minimizing the need for any wired connections, and in turn, combining data connectivity with user mobility.1 WLANs provide all the functionality of WLANs without the physical constraints, and configurations range from simple peer-to-peer topologies to complex networks offering distributed data connectivity and roaming. Besides offering end-user mobility within a networked environment, WLANs enable physical network portability, allowing LANs to move with users that make use of them.

The tradeoff for flexibility and mobility is more threats from hackers using portable computing devices or scanners to intercept data or gain access to the LAN. Unwired LANs are more susceptible to attacks by outside forces via the Internet than wired LANs are. A hacker can crack a network from the convenience of his or her car parked nearby the location of the WLAN. IEEE 802.11, the WLAN standard, provides reliable transfer of wireless data but is vulnerable to hacking or eavesdropping.2

In fourth quarter 1999 and first quarter 2000, a collection of reputable vendors brought to market a host of 802.11b-compliant products. The void that IT managers had been facing was finally filled with high speed, interoperable, insecure, and lowercost wireless equipment.3 Many IT operations justified the loss of security on the tradeoff for ways to inject mobility, flexibility, and scalability into their networks.