From GSM to LTE-Advanced: An Introduction to Mobile Networks and Mobile Broadband, Revised Second Edition

Chapter 5Wireless Local Area Network (WLAN)

In the mid-1990s, the first Wireless Local Area Network (WLAN) devices appeared on the market, but they did not get a lot of consumer attention. This changed rapidly at the beginning of this decade, when the hardware became affordable and WLAN quickly became the standard technology to interconnect computers, and later smartphones and tablets also wirelessly interconnected with each other and the Internet. This chapter takes a closer look at this system, which was standardized by the Institute of Electrical and Electronics Engineers (IEEE) in the 802.11 specification [1].

The first part of this chapter describes the fundamentals of the technology. Once the system became popular, a number of inherent security flaws were discovered and fixed. The chapter therefore also focuses on these issues and shows how WLAN can be used securely. And finally, this chapter also takes a look at the functionalities that were introduced in the subsequent versions of the specification.

5.1 Wireless LAN Overview

Wireless LAN received its name from the fact that it is primarily based on existing LAN standards. These standards were initially created by the IEEE for wired interconnection of computers and can be found in the 802.X standards (e.g., 802.3 [2]). In general, these standards are known as ‘Ethernet’ standards. The wireless variant, which is generally known as Wireless LAN, is specified in the 802.11 standard. As shown in Figure 5.1, its main application ...