Evolution-Cast: Temporal Evolution in Wireless Social Networks and Its Impact on Capacity

This paper characterizes an evolving network with growing number of nodes, which are associated with each other through social relations but employ transmission via wireless communications. The network exhibits social relations between nodes by attaching a new arriving node to a sample node already existing as well as some nodes the sample directly links to. We study capacity in this evolving network in terms of both geographic distribution of nodes and traffic patterns. Our results show that in heterogeneous geographic distribution where nodes having strong social relations tend to locate more closer, the corresponding capacity is significantly impacted by both social relations and network evolution. In particular, with appropriate control on the initial number of nodes as well as links between them, it is even possible to achieve almost constant per-node capacity except for a poly-logarithmic factor. For homogeneous geographic topology where nodes´ positions exhibit uniform distribution, social relations among nodes is useless for improving capacity, which is mainly affected by network evolution and therefore degrades sharply with time. To our best knowledge, this is the first work studying capacity from the perspective of social evolving network.