From GSM to LTE: An Introduction to Mobile Networks and Mobile Broadband

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 (WLAN), is specified in the 802.11 standard. As shown in Figure 6.1, its main application today is to transport IP packets over layer 3 of the OSI model. Layer 2, the data link layer, has been adapted from the wired world with relatively few changes. To address the wireless nature of the network, a number of management operations have been defined, which are described in Section 6.2. Only layer 1, the physical layer, is a new development, as WLAN uses airwaves instead of cables to transport data frames.

Figure 6.1 The WLAN protocol stack.