Evaluation of packet scheduling algorithms in mobile ad hoc networks

Abstract

We examine the queuing dynamics at nodes in an ad hoc mobile network and evaluate network performance under different packet scheduling algorithms using Dynamic Source Routing (DSR) and Greedy Perimeter Stateless Routing (GPSR) as the underlying routing protocols. Typically, packet schedulers in ad hoc networks give priority to control packets over data packets and serve data packets in FIFO order. We find that setting priorities among data packets can decrease end-to-end packet delay significantly. In particular, we find that among the algorithms we studied, those that give priority to data packets with short distance metrics show the smallest delay and the highest throughput, without increasing routing overhead. In addition, we show that with both DSR and GPSR, giving priority to control packets over data packets affects the performance significantly when mobility is high. With DSR, giving priority to control packets reduces the average delay. In contrast, with GPSR, this scheduler increases the average delay.