A Novel Delay Tolerant Routing Protocol for Opportunistic Networks

Delay Tolerant networks (DTNs) belong to a class of wireless networks which are designed specifically for environments where high latency, frequent disruptions and intermittent connectivity is seen. Such type of networks rely on a store-forward-carry mechanism in contrast to a store and forward mechanism as seen in MANETs and adhoc networks. In this paper we have attempted to propose a variant of Spray and Wait protocol based on the Catalan series. The Catalan spray and wait protocol converges faster than its binary counterpart and hence can find its applicability in applications with a higher packet delivery ratio at minimal cost. Simulation of real life scenario of cars and pedestrians moving on a map is used to show the working and efficacy of our proposed routing model. The Catalan algorithm outperforms the Binary Spray and Wait in term of metrics viz. delivery ratio, overhead ratio and average buffer time. It showcases a reduced overhead ratio of 21% when compared to the binary version of 24% for no of copies L = 18. The average buffer size and the number of copies used for 100, 500, 1000, and 2000 nodes are analyzed and the Catalan routing protocol exhibits a decrease of 0.1%, 1.5%,1.35%,1.38% (for last values) in average buffer occupancy as compared to the binary version. Moreover, it shows an overall average increase of 3% over Hexago and Pentago protocol in terms of delivery ratio.