An Adaptive Mechanism for High Efficiency and Fairness in IEEE 802.11 Wireless Lans

Wireless local area networks own their popularity mainly to the robust characteristics of distributed medium access schemes. However, as new user applications diverge from the traditional data-centric model, the introduction of distributed medium access methods that achieve high efficiency in terms of both throughput and fairness becomes of utmost importance. IEEE 802.11 is the most widely used access scheme for wireless networks. In this paper, we address a shortcoming of IEEE 802.11 as indicated by previous studies, namely the inability of the protocol to adapt to different working conditions. We study and evaluate a low complexity mechanism that allows a network employing the IEEE 802.11 protocol to adapt its operating parameters according to the offered load. Simulation studies further document and confirm the high throughput and fairness performance of the proposed scheme.