The Institute of Electrical and Electronics Engineers, Inc. (IEEE) is currently developing the IEEE 802.11e (802.11e) as an extension of the IEEE 802.11 wireless Local Area Network (LAN) standard, to enable wireless LANs to achieve higher data throughput and lower delay constraints, hence, to support Quality of Service (QoS). By applying 802.11e, stations are able to carry multimedia and Internet applications with QoS. Home networks with their characteristic applications such as voice, video, and interactive data, typically require QoS. This thesis provides an overview about this new standard, and analyzes the limits of 802.11e in various network configurations. The new coordination function of the 802.11e Medium Access Control (MAC) is described and analyzed, where a variety of enhancements of 802.11e are evaluated by means of analytical approximation and stochastic simulation.
The problem of QoS support in coexistence scenarios of overlapping Basic Service Sets (BSSs), i.e., co-located sets of communicating 802.11e stations, is discussed. In an isolated scenario of one single BSS, QoS is guaranteed by one central coordinator polling other stations for data transmission, similar to the European wireless LAN High Performance Local Area Network type 2 (HiperLAN/2). In a coexistence scenario of overlapping BSSs, stations cannot guarantee any QoS because of the uncoordinated access to radio resources. Any utilization of radio resources by a BSS depends on the activities of competing BSSs. The approach developed in this thesis to allow BSSs to support and guarantee QoS is to apply models derived from the theory of games. The models are used to analyze the mutual influence of coexisting BSSs, and to define means for interaction
based on actions, utility functions, and payoffs. The competition scenario is modeled as game, and evaluated with a Nash analysis. In a game, a BSS is
modeled as player that attempts to maximize its payoff, which is an abstract representation of QoS.