Scheduling of real-time traffic in IEEE 802.11 wireless LANs

The desire to provide universal connectivity for mobile computers and communication devices is fueling a growing interest in wireless packet networks. To satisfy the needs of wireless data networking, study group 802.11 was formed under IEEE project 802 to recommend an international standard for Wireless Local Area Networks (WLANs). A key part of the standard are the Medium Access Control (MAC) protocols. Given the growing popularity of real-time services and multimedia based applications it is critical that the 802.11 MAC protocols be tailored to meet their requirements. The 802.11 MAC layer protocol provides asynchronous, time-bounded, and contention free access control on a variety of physical layers. In this paper we examine the ability of the point coordination function to support time bounded services. We present our proposal to support real-time services within the framework of the point coordination function and discuss the specifics of the connection establishment procedure. We conduct performance evaluation and present numerical results to help understand the issues involved.