Call admission control for IEEE 802.11 contention access mechanism

This paper proposes an admission control algorithm that enables the upcoming IEEE 802.11e contention based Enhanced Distributed Channel Access (EDCA) to provide quantitative bandwidth guarantees for Wireless Local Area Networks (WLANs), rather than a relative prioritized service. The algorithm estimates the throughput that flows would achieve if a new flow with certain parameters was admitted, and so indicates whether such a new flow can be admitted while preserving the Quality of Service (QoS) of existing flows. The algorithm deals with the EDCA parameters of minimum contention window size and transmission opportunity duration, and indicates what values should be used for different flows. Simulation results confirm the accuracy of the throughput estimates and the effectiveness of the admission control algorithm.