Wireless sensor networks (WSN) is widely used for gathering data in the distributed fashion. In WSN, each node has limited energy resource, and thus the lifetime of the network is one of the most critical issues. In this paper we propose an energy efficient and optimal randomized clustering protocol for selforganizing WSNs. The proposed scheme decides optimal number of clusters by employing a new approach for setting threshold value, including the probability of optimum number of clusterheads and residual energy of the nodes. We also introduce a new approach maximize the network lifetime by tree construction in each cluster. Computer simulation shows that the proposed scheme effectively reduces and balances the energy consumption among the nodes, and thus significantly extends the network lifetime compared to the existing schemes.

In this paper we propose an energy efficient clustering algorithm for maximizing the lifetime of WSNs. The proposed scheme decides the cluster head based on the energy level of the nodes, while tree topology is adopted to connect the nodes inside each cluster. A new model for deciding an optimal number of clusters is also derived. Computer simulation reveals that the proposed scheme significantly extends the network lifetime and message delivery ratio compared to the existing schemes.