Overlapping Clusters Algorithm in Ad Hoc Networks

Clustering allows efficient data routing and multi-hop communication among the nodes. In this paper, we propose Overlapping Clusters Algorithm (OCA) for mobile ad hoc networks. The goal of OCA is to achieve network reliability and load balancing. The algorithm consists of two discrete phases. The start-up phase takes battery and bandwidth capacity, transmission range, density, mobility, and buffer occupancy as input parameters to performs initial clustering for the entire network. The maintenance phase monitors the status of the network and keeps the network topology updated through local and global re-clustering. We compare the performance of OCA with Lowest ID, Highest Degree, WCA, and LCC algorithms in YAES simulator. The simulation results show that OCA outperforms all the compared algorithms in terms of network reliability and load distribution. The average numbers of global re-clusterings and reaffiliations were much lower in OCA than the other algorithms. However, OCA generates a larger number of clusters, which is expected considering that the nodes are allowed to be members of multiple clusters at the same time.