A Priority-based QoS Routing Protocol with Zone Reservation and Adaptive Call Blocking for Mobile Ad Hoc Networks with Directional Antenna

Abstract — Existing priority-based QoS routing protocols in ad hoc wireless networks did not consider the effect of mutual interference between routes in wireless medium during routing. We have investigated the effect of mutual interference on the routing performance in wireless environment and explored the advantage of using zone-disjoint routes to avoid mutual interference and to improve the network performance. In this paper, a priority based QoS routing scheme is proposed that uses the notion of zone-disjoint routes. Our protocol avoids the contention between high and low priority routes by reserving high priority zone of communication. Low priority flows will try to avoid this zone by selecting routes that is maximally zonedisjoint with respect to the high priority reserved zone and will consequently allow a contention-free transmission of high priority traffic in that reserved zone. If, under some unavoidable situations, a low priority flow has to go through high priority reserved zone causing interference then it will block itself temporarily to allow contention-free transmission of high priority flows and later may resume the blocked communication if possible. We have evaluated the effectiveness of our proposed protocol on QualNet network simulator. Keywords-Ad hoc networks; Directionl Antenna; Priority-based QoS;Zone-disjoint routes; Zone-reservation; Call-blocking