In recent years, the demand for rendering multimedia applications over wireless has motivated the development and enhancement of IEEE 802.11 wireless local area network (LAN). Compared to the traditional Ethernet LAN, Wireless LAN has the merits of easy installation, low cost and supporting certain degree of mobility. 802.11 is a part of the 802 standard family for local area networks. This family defines the physical and data link layer specified in the International Organization for Standization (ISO) Open Systems Interconnection (OSI) basic reference model. More specifically, 802.11 defines the medium access control (MAC) layer and physical (PHY) layer. Its relation with other IEEE 802 standards is illustrated in Figure 8.1.
The illustrated standards in Figure 8.1 are described as follows: