A Hidden Node Aware Network Allocation Vector Management System for Multi-hop Wireless Ad hoc Networks

Abstract

Many performance evaluations for IEEE 802.11<br />distributed coordination function (DCF) have been previously<br />reported in the literature. Some of them have clearly indicated<br />that 802.11 MAC protocol has poor performance in multi-hop<br />wireless ad hoc networks due to exposed and hidden node<br />problems. Although RTS/CTS transmission scheme mitigates<br />these phenomena, it has not been successful in thoroughly<br />omitting these drawbacks. We argue that when eliminating<br />hidden node effect with a given protocol is not feasible, one<br />may sometimes earn more throughput by controlling or even<br />wisely creating this phenomenon. In this paper we propose a<br />novel solution to improve the performance of IEEE 802.11<br />MAC protocol in multi-hop networks through modifying NAV<br />timer. We may call this method Dynamic NAV (DNAV) since<br />the NAV timer operation changes dynamically with the change<br />of environment variables. Simulation results show that our<br />approach noticeably increases the throughput in multi-hop<br />wireless ad-hoc networks.