N-BEB: New backoff algorithm for IEEE 802.11 MAC protocol

Abstract

IEEE 802.11 standard primarily utilizes Distributed Coordination Function (DCF) which is based on carrier sense multiple access with collision avoidance (CSMA/CA). IN DCF, when a collision occurs, then a backoff algorithm will take place to randomize medium access for the nodes. The default backoff mechanism used in 802.11 is the binary exponential backoff (BEB) algorithm. In this paper, we analyze the behavior of various backoff algorithms used in IEEE802.11 standard: BEB, I-BEB, and E-BEB, then we propose the New Binary Exponential Backoff (N-BEB) algorithm to improve channel access fairness while preserving the channel throughput. Our N-BEB algorithm improves the selection process of the contention window CW, based on the number of successful and unsuccessful transmissions. Simulation results confirm fairness improvement, power consumption enhancement, reduction of dropped packets and high delivery ratio for proposed protocol over BEB, I-BEB, and E-BEB protocols.