Social-tie-based information dissemination in mobile opportunistic social networks

A mobile opportunistic social network (MOSN) is a new type of delay tolerant network (DTN), in which the mobile users contact each other opportunistically. Information dissemination is a challenging problem in MOSNs, due to uncertainty and intermittent connectivity. In this paper, we propose a distributed social tie strength calculation mechanism to identify the relationship between each set of pairwise mobile nodes. Following arguments originally proposed by Mark Granovetter's seminal 1973 paper, The Strength of Weak Ties, the majority of the novel information dissemination is generated by weak ties. We first evaluate the strength of weak ties in MIT reality mining data. Then, a social-tie-based information dissemination protocol is presented, which is a token-based information dissemination scheme, including two phases: weak tie-driven forwarding and strong tie-driven forwarding. In the weak tie-driven forwarding phase, the susceptible nodes with more weak ties will receive more tokens for future forwarding. The number of forwarding tokens is related to the number of weak ties of two encountered nodes. After a while, the information will have been spread to multiple communities. Our scheme switches to a strong tie driven forwarding phase, in which the influential nodes are more important. The number of forwarding tokens is proportional to the number of strong ties of two encountered nodes. Extensive simulations are conducted in comparison to several approaches in real world mobile traces.