paratively little attention. Priority sched- uling is particularly adapted to real-time traffic such as streaming audio or video. Shakkottai and Srikant have attempted to modify the earliest deadline due (EDD, like EDF algorithm) to function over a wireless channel. 33 Their algorithm uses a finite-state Markov channel model³ to represent "good" and "bad" channels. In contrast, Veciana and Yang have dis- cussed a way of improving user perceived performance for best effort traffic. 35 Yaxin and Zhigang Cao have combined real-time and best effort traffic scheduling. In the scheme of joining multiple algorithms to serve different traffic types, we also find research by Wongthavarawat and Ganz, which deals specifically with traffic scheduling for an 802.16/WiMAX network, from a QoS perspective. 37 The paper is novel in merging together multiple wireline algorithms for 802.16 traffic scheduling, and in considering the uplink scheduling, which has thus far been largely ignored. However, no attempt is made to enhance any of these algorithms specifically for wireless systems, or to take advantage multiuser diversity. A similar paper that compiles three different algorithms to serve different traffic types for an 802.16/WiMAX network is presented by Chu et al. in Ref. 38 Their proposal combines a wireless packet scheduling algorithm for real-time services with a weighted-RR for nonreal-time services and a First-In-First-Out for best effort services. A paper that focuses on real-time VoIP traffic is presented by Lee et al. 39 The proposal uses a special bit in the MAC header to implement a proprietary scheduling scheme for VoIP traffic in an 802.16 network. The authors claim that this method achieves better performance than if VoIP traffic were mapped on real-time connections with implied grants. Lee et al.'s algorithm could be combined with a scheme presented by Kim et al., which focuses on a nonreal-time scheduler with a minimum bit rate. 40 This proposal could be used to manage nonreal-time services flows. The authors c