Modeling Instant Messaging group network

The Instant Messaging (IM) is the major form of communication system. The topology of IM network has been proved as a scale-free, but the group feature which added into I M system recently was not consider in the previous work. On the other hand, the correct topology of IM is important in the analysis of IM communication and security. We argue that the group feature is quite different from the IM origin topology. Motivated by this, we study the IM group topology for the first time, where two IM users are considered connected if they are in one or more same groups. We investigate a variety of statistical properties of the IM group network: numbers of members per group, numbers of groups per user, numbers of links per user, giant component, path length, and clustering coefficients. Because there is no model can generate the topology of IM group network, we propose a new incremental topology generator Group Limit Generator (GLG). The result of experiment shows that the GLG is successful at matching the power law exponent, path length, and the clustering behavior of the IM group network.