Data routing strategies in opportunistic mobile social networks: Taxonomy and open challenges

Opportunistic Mobile Social Network (MSN) is a kind of Delay Tolerant Network (DTN) in which nodes are mobile with social characteristics. Users in such network carry data, move and forward it to others for information dissemination. To enable efficient data routing in opportunistic MSNs, the social metrics of users, such as mobility pattern, social centrality, community and etc. are leveraged in context of MSNs. In this paper, we investigate the data routing strategies in opportunistic MSNs in the following aspects: (1) the architecture of MSNs and its routing challenges and (2) routing strategies investigation on the basis of different social metrics. We study opportunistic MSN architecture and investigate the social metrics from encounter, social features and social properties, respectively. We show that encounter information is important exemplification of social metrics in opportunistic MSNs. We present other social metrics such as social features and social properties, including social graph properties and community structure. We then elaborate the routing strategies from different perspectives accordingly: encounter-based routing strategies, routing schemes according to social features and routing strategies based on social properties. We discuss the open issues for data routing in opportunistic MSNs, including limitations of routing metrics, collection of social information, social privacy and security, future applications of opportunistic MSNs, and etc.