Adaptive EY-NPMA: A medium access protocol for wireless LANs

Wireless local area networks have known an increasing popularity during the past few years. However, as new user applications diverge from the traditional data-centric model, the introduction of efficient, QoS aware medium access methods becomes of utmost importance. EY-NPMA is a medium access protocol belonging to the contention paradigm that provides support for service differentiation and low collision rates. In this paper, we address a shortcoming of EY-NPMA as indicated by previous studies, namely the insensitivity of the protocol to different working conditions. In this work, we study and evaluate a mechanism that allows a network employing EY-NPMA to adapt its operating parameters according to the offered load. Simulation studies further document and confirm the positive characteristics of the proposed mechanism.