Disseminating real-time messages in opportunistic mobile social networks: A ranking perspective

There has been a significant body of work on evaluating node criticality in information networks. However, most of the existing works are developed for static networks and are not applicable to dynamic settings where connectivities among nodes change frequently over time. In this paper, we treat an opportunistic mobile social network as a time-evolving, dynamic graph, and propose a scheme to ascertain the information dissemination capability for each node based on its contact history. In particular, we analyze the node importance in spreading or forwarding real-time messages which are assumed to become less important or even stale over time. To this end, we take a dynamic walk counting approach to calculate all possible temporal-spatial routes associated with each node, by using the down-weighting method. Since the age of a message increases with time, the old walks are discounted to represent the fading influence on the target node. Extensive experiments are conducted based on 4 real-world trace datasets, and the results show that, our analytical result is effective at ranking the node criticality in disseminating or acquiring real-time messages in opportunistic mobile social networks.