RETT-gen: A globally efficient routing protocol for wireless sensor networks by equalising sensor energy and avoiding energy holes

Abstract

Wireless sensor networks are composed of a large number of sensor nodes with limited energy resources. Once deployed, the sensor nodes are usually inaccessible to the user, and thus replacement of the energy resource is not feasible. Hence, energy efficiency is a key design issue that needs to be enhanced in order to improve the life span of the entire network. Several routing protocols have been proposed to improve the effective lifetime of the network with limited energy supply. In this paper, we propose routing based on energy–temperature transformation, RETT-gen, a scalable energy-efficient clustering and routing protocol designed for wireless sensor networks. The main goal of RETT-gen is to evenly distribute the energy load among all the sensor nodes in the network so that there are no overly-utilized sensor nodes that will run out of energy before the others. To achieve this goal, RETT-gen uses heat conductivity as a metaphor and uses the heat dissipation difference equations. In RETT-gen, we transform the expected lifetime of each sensor node to an equivalent temperature, and then by using the heat dissipation equations, we find the hottest path for sending data to the base station, which will not always be the shortest path. We evaluate the performance of the RETT-gen protocol via simulations, and compare it to the performance of well-known routing protocols (i.e. LEACH [W. Heinzelman, A. Chandrakasan, H. Balakrishnan, Energy-efficient communication protocol for wireless microsensor networks, in: Proceedings of the 33rd Hawaii International Conference on System Sciences (HICSS’00), 2000.] and EEUC [C. Li, M. Ye, G. Chen, J. Wu, An energy-efficient unequal clustering mechanism for wireless sensor networks, in: Proceedings of the International IEEE Conference on Mobile Adhoc and Sensor Systems (MASS), 2005.]). Simulation results show that by equalizing the sensor nodes energy, RETT-gen insures that the lifetime of the entire sensor network is maximized, the connectivity in a sensor network is maintained for as long as possible, and that the residual energy of the entire network is of the same order.