From GSM to LTE-Advanced Pro and 5G, 3rd Edition

6 Wireless 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 10 years later, when the hardware became affordable and WLAN quickly became the standard technology for connecting computers, smartphones and tablets to 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, which have changed little since the beginning. In the second part, the chapter describes the evolutionary steps that were taken over time to increase transmission speeds. In the final part, security features are described as well as a number of optional functionalities.

6.1 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 6.1, its main application today is to transport Internet Protocol (IP) packets over layer 3 of the ISO model. Layer 2, the data link layer, has been ...