Face-to-face with Facebook Friends: Using Online Friendlists for Routing in Opportunistic Networks

Opportunistic networks are a generalization of Delay Tolerant Networks (DTNs) where communication is challenged by frequent disconnections and encounter patterns between mobile devices are unpredictable. Opportunistic routing protocols attempt to enable the forwarding of messages via encounters between devices, while dealing with the problems of large delays and lack of end-to-end connectivity. To save energy in mobile environments, such routing protocols must minimize unnecessary message replication. This paper presents FSF (Friendlist-based Social Forwarding), an opportunistic routing scheme that exploits both social network information detected through encounters between mobile devices and pre-existing online social network information. To select an effective forwarding node, FSF measures the forwarding capability of a node when compared to an encountered node in terms of node degree centrality measured on the temporal encounter network and online tie strength. Simulations with experimental datasets containing encounter records with corresponding Facebook friendlists of the participants show that the proposed routing scheme allows mobile users to achieve good delivery ratio, while forwarding fewer messages than other existing algorithms.