Optimized tuning of contention window for IEEE 802.11 WLAN

Abstract

In wireless networks, the size of Contention Window (CW) plays a vital role as it changes the throughput and delay of the networks considerably. The proposed Collision Ratio based BackOff (CRBO) algorithm uses collision ratio to suggest CW updation after the successful and unsuccessful transmission events. This leads to proper scheduling of transmission when more than one node attempt to capture the shared medium. The strength of the proposed algorithm is analyzed using NS2 simulator in terms of throughput, delay, packet loss and fairness. The simulation results prove that the proposed algorithm outperforms the existing algorithms under heavy and low traffic in random and grid topology.

Keywords: Wireless networks, contention window, collision rate, backoff, NS2