Closeness-based routing with temporal constraint for mobile social delay tolerant networks

In mobile social delay tolerant networks, many human-carried mobile devices are moving around in a restricted physical space and occasional contact opportunities among these devices are used to deliver data. Routing design in mobile social delay tolerant networks has been a challenging task due to lack of instantaneous end-to-end paths, large transmission delays, and time-varying network topology. In this paper, aiming to precisely measure the social relationships between mobile nodes, we introduce two kinds of time-varying closeness, direct and indirect closeness, where the temporal constraint is considered. Then we propose both single-copy and multi-copy closeness-based routing schemes, which consider direct and indirect social relationships under temporal constraint. Extensive simulations on real-life data traces show the proposed schemes can achieve better performances than existing DTN routing methods.