Sensor networks are highly distributed networks of small and lightweight wireless nodes. In Wireless sensor networks, nodes have limited energy resources and, consequently, protocols designed for sensor networks should be energy-efficient. The decrease of the received power at the receiving nodes increases the probability of bit error and of packet loss. Alternatively, the sender nodes can use larger transmission power for the same probability of bit error, thus increasing the energy consumption. This allows the sensor to use more energy and the transmission that maximizes the energy consumption and decreases the transmission reliability. We model a cluster based approach to minimize the energy consumption by the cluster establishment and thereby increasing the reliability of packet delivery. © 2012 Pillay Engineering College.