Improving the Performance of Delay Tolerant Mobile Networks by Prioritizing Buffered Packet

The conventional routing protocols are not able to handle intermittent mobile networks, since because of deficiency of nodes’ density, mobility, instability of radio connections, most of the times no path exists among the source and destination nodes. Delay tolerant networks (DTN) is a solution in which communications become feasible in intermittent mobile networks by tolerating long delays. Routing methods in DTN use the idea of spreading packets among the mobile nodes for transporting information toward the destinations. In order to achieve a good performance, it is necessary to control the workload of the network by limiting the number of copies. In this paper, a novel method for packet copying process is proposed which improves the throughput significantly while controlling the workload of the network. The key idea behind the proposed method is to prioritize the buffered packets at each node in order to avoid excessive repetitions of packets and stop wasteful workload grow. The packets are prioritized based on the source nodes, the ages, and their remaining lifetimes. Our simulation results indicate that the proposed method can improve packet delivery ratio by 40 to 60 percent in comparison with Spray and Binary Wait, and Direct delivery routing methods.