Enhancing Cluster Head Election Scheme through Load Balancing for Improving Stability in Mobile Ad Hoc Networks

Nodes in MANET operate not only as an end system, but also as a router to forward packets. These nodes moves free and organizes themselves into a network. They also change its position frequently. To accommodate the changing topology special routing algorithms are needed. In a flat topology, all nodes are of the same level with equal functionalities. Therefore, flat routing protocols are sufficient only for small networks. Scalability is hard to achieve when the network size increases. In such a case, cluster based routing strategy can be a good choice. In a cluster-based routing, all nodes in the network are dynamically organized into partitions called groups or clusters. These clusters are then combined into larger partitions to help maintain a relatively stable network topology. One of the most critical issues in these networks is load imbalance among cluster heads. Thus, sharing the load between the overloaded and idle cluster heads is necessary in ad hoc networks. Because, these cluster heads has more responsibility and deplete more energy; thus drops out of the network soon. Therefore, there is a need for load-balancing among cluster heads to allow all nodes to serve as a cluster head. We propose a load balancing heuristic to extend the life of cluster heads. The simulation results show that the proposed heuristic guarantees fairness and stability.