ABSTRACT
Wireless networks are generally less efficient and unpredictable compared to wired networks, which make quality of service (QoS) provisioning a bigger challenge for wireless communications. The wireless medium has limited bandwidth, higher packet error rate, and higher packet overheads that altogether limit the capacity of the network to offer guaranteed QoS. In response to the increasing QoS challenge in wireless networks, researchers have made significant modifications in the legacy IEEE 802.11 standards to facilitate QoS to end users. The design constraints at several layers of the IEEE 802.11, however, restrict its capacity to deliver guaranteed QoS. Recently, the IEEE 802.16 standard, also known as worldwide interoperability for microwave access (WiMAX), has emerged as the strongest contender for broadbandwireless technologywith promises to offer guaranteed QoS
to wireless application users. In this chapter, the details of QoS framework in WiMAX technology are presented. The definition of QoS as well as the legacy wireless QoS framework is presented first. The key technological strengths of WiMAX to address QoS challenges are identified. We present the details of WiMAX QoS mechanisms and finally conclude the chapter by identifying some open research issues.
