Traffic dynamic in modularity structure of complex networks.

Modularity structure is often found in many different types of complex networks. Especially, this topological property is believed to provide a certain degree of robustness to networks. This belief leads us naturally to investigate the impact of modularity structure on the behavior of networks. In this paper, we carry out two simulation studies to monitor traffic dynamic in modularized and non-modularized power law networks. In the first simulation, coarse-grained traffic is flooded through networks. This study demonstrates that a modularized structure localizes damages and stops the malicious effect to the whole system. In the second simulation, more finegrained traffic is used to investigate how a modularity structure impacts on the saturation of networks. This result shows that a strong modularity structure is saturated much faster than nonmodularized topology as traffic load increases, and additionally we show how this early saturation in modularized structure can be overcome.