Effect of packet scheduling and evaluation of fuzzy based priority scheduler on ad hoc network unicast communication

In mobile ad-hoc network, the mobility of nodes and the error prone nature of the wireless medium pose many challenges and packet losses. Here, since the nodes are mobile, the network topology changes rapidly and unpredictably over time and produce different queuing behaviour. Hence, a scheduling algorithm to schedule the packets based on their respective priorities will improve the performance of the network. Typically, packet schedulers in ad hoc networks give priority to control packets over data packets and serve data packets in FIFO order. Here, we present an fuzzy based priority scheduler for mobile ad-hoc networks, to determine the priority of the packets using dynamic source routing (DSR), ad hoc on demand distance vector routing (AODV) and wireless routing protocol (WRP) as the underlying unicast routing protocols. We find that setting priorities among data packets decrease the end to end delay significantly. The performance of this scheduler is studied using GloMoSim and evaluated in terms of quantitative metrics such as packet delivery ratio, average end to end delay and throughput. It is found that the scheduler provides overall improvement in the performance of the system, when tested with different unicast routing protocols under different mobility conditions.