Routing with multi-level social groups in mobile opportunistic networks

Mobile Opportunistic Networks (MONs) are intermittently connected networks, such as pocket switched networks formed by human-carried mobile devices. Routing in MONs is very challenging as it must handle network partitioning, long delays, and dynamic topology. Flooding is a possible solution but with high costs. Most existing routing methods for MONs avoid the costly flooding by selecting one or multiple relays to deliver data during each encounter. How to pick the 'good' relay from all encounters is a non-trivial task. To achieve efficient delivery of messages at low costs, in this paper, we propose a new group-based routing protocol in which the relay node is selected based on social group information obtained from historical encounters. We apply a simple formation method to build multi-level social groups, which summarizes the wide range of social relationships among all mobile participants. Our simulations demonstrate the efficiency and effectiveness of the proposed method by comparing it with several existing MON routing schemes.