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

Many performance evaluations for IEEE 802.11distributed coordination function (DCF) have been previouslyreported in the literature. Some of them have clearly indicatedthat 802.11 MAC protocol has poor performance in multi-hopwireless ad hoc networks due to exposed and hidden nodeproblems. Although RTS/CTS transmission scheme mitigatesthese phenomena, it has not been successful in thoroughlyomitting these drawbacks. We argue that when eliminatinghidden node effect with a given protocol is not feasible, onemay sometimes earn more throughput by controlling or evenwisely creating this phenomenon. In this paper we propose anovel solution to improve the performance of IEEE 802.11MAC protocol in multi-hop networks through modifying NAVtimer. We may call this method Dynamic NAV (DNAV) sincethe NAV timer operation changes dynamically with the changeof environment variables. Simulation results show that ourapproach noticeably increases the throughput in multi-hopwireless ad-hoc networks.