A performance comparison of delay-tolerant network routing protocols

Abstract

© 1986-2012 IEEE. Networks that lack continuous end-to-end connections among their nodes due to node mobility, constrained power sources, or limited data storage space are called DTNs. To overcome the intermittent connectivity, DTN nodes store and carry the data packets they receive until they come into communication range of each other. In addition, they spread multiple copies of the same packet on the network to increase the delivery probability. In recent years, several routing protocols have been developed specifically for DTNs. These protocols vary in the number of copies they spread and the information they use to guide the packets to their destinations. There have been some reviews of those protocols, but no performance comparison has been conducted. In this article, we study four well-known DTN routing protocols: EPIDEMIC, Spray-and-Wait, PROPHET, and MAXPROP. We introduce a procedural form to present the protocols. We measure the performance of the protocols in terms of packet delivery, delivery cost, and average packet delay. We compare the protocols' performance together with the results of optimal routing using real-life scenarios of vehicles and pedestrians roaming in a city. We conduct several simulation experiments to show the impact of changing buffer capacity, packet lifetime, packet generation rate, and number of nodes on the performance metrics. The article is concluded by providing guidelines to develop an efficient DTN routing protocol. To the best of our knowledge, this work is the first to provide a detailed performance comparison among the diverse collection of DTN routing protocols.