ABSTRACT
Th e IEEE 802.16 is a mature standard for fi xed broadband wireless access (BWA), where a single Base Station (BS) coordinates the access to the wireless medium of many Subscriber Stations (SSs) in a frame-based centralized manner. Th e standard specifi es that the BS is responsible for providing the traffi c fl ows of SSs with quality of service (QoS), in terms of a set of negotiated parameters. To this aim several mechanisms are defi ned at the Medium Access Control (MAC) layer. However, the standard does not specify the procedures that should be employed by the BS and SSs so as to enforce the negotiated level of QoS. In this work the mechanisms available for QoS support are reported in details, in the context of QoS architecture of IEEE 802.16. Furthermore, the approaches that have been proposed in the literature so far for QoS support are reviewed. Due to high level of complexity of the IEEE 802.16, most proposed solutions have been evaluated using simulation, whose results are summarized here. Finally, a simulation analysis is carried out, so as to
evaluate the performance of diff erent multimedia applications, with varying number of users and MAC frame duration.
