Autonomous Clustering Scheme for Removing the Effects of Heterogeneous Node Degrees in Ad Hoc Networks

In large scale mobile ad hoc networks (MANETs), it is effective to reduce the load of routing by introducing hierarchical routing, and it is conducted by clustering of nodes. A clustering mechanism based on the diffusion equation is a typical autonomous clustering in MANETs, and gives appropriate clustering if all the node degrees are uniform. However, node degrees in MANETs are heterogeneous in general, the fact causes the difference in the strength of diffusion effect. This difference causes that the position of cluster head tends to be around the boundary of networks and degrade battery efficiency of nodes. In this paper, by introducing an asymmetric diffusion depending on node degree, we propose a new clustering method independent of heterogeneity of node degrees. We show that the proposed method has efficient characteristics for battery consumption. In addition, we show the comparison of the proposed method with the conventional method with respect to the efficiency of routing.