1SMART: A Social and Mobile Aware Routing Strategy for Disruption Tolerant Networks

Abstract—Disruption tolerant networks (DTNs) are sparse mobile ad hoc networks where nodes connect with each other intermittently and end-to-end communication paths do not exist. Data routing in DTNs is challenging and draw much atten-tion from research communities recently. Although many DTN routing strategies have been proposed in the past years, they confront problems such as blind spot and dead end, and also lack of efficient implementation in a decentralized, large-scale, mobile, and dynamic environment. To overcome these difficulties, we introduce a new solution for DTNs which leverages social properties and mobility characteristics of users. Our observation to the mobile trajectories of three data sets collected from real DTNs reveals that user movements appear locality and they tend to form communities correlated to geographic locations. Based on these findings, we propose a Social and Mobile Aware routing sTrategy (SMART). It exploits a distributed community partitioning algorithm to divide the DTN into smaller communi-ties regarding user locations and interaction routines. For intra-community communication, a decayed routing metric convoluting social similarity and social centrality is calculated, which is used to decide forwarding node efficiently while avoiding the blind spot and dead end problems. To enable efficient inter-community communication, we choose the fringe nodes which travel remotely as relays, and propose the node-to-community utilities for routing decision across communities. We present empirical analysis to show that SMART reduces the occurrence of blind spot and dead end to a level below 1%. The efficiency of SMART is evaluated by extensive trace-driven experiments, which illustrate that it outperforms other routing strategies in various real DTN traces. I