IEEE 802.16 WiMAX (Worldwide Interoperability for Microwave Access) is a major standard technology for Wireless Metropolitan Area Networks (Wireless MAN). Quality-of-service (QoS) scheduling class and mobility management are two main issues for supporting seamless high-speed data and media-stream communications. Previous works on WiMAX handoff however have mainly addressed a particular scenario or a single QoS class. This chapter first presents an overview of the QoS scheduling classes supported by the IEEE 802.16 standard, followed by a survey of major related works proposed to enhance 802.16e handoffs. Next, it will present a new context-sensitive handoff scheme that supports the five 802.16 QoS scheduling classes, and is energy-aware – it may switch to energy-saving mode during handoff. It will then illustrate performance evaluation, which will show that, compared to three existing methods, the proposed scheme successfully supports the five QoS classes in both layers 2 and 3 handoff, decreases end-to-end handoff delay, delay jitter, and service disruption time; it also increases throughput and energy efficiency. Finally, key implementation and cost issues are discussed. We believe that this chapter is a significant contribution for providing high-quality, seamless data and media streaming over 802.16 as well as LTE (Long-Term Evolution) cellular networks, and would be a valuable part of QoS architectures in the wireless networking domain.
Call admission control scheme with normalized quality of service metric in IEEE 802.16 networks
