CRP: Cluster head Re-election Protocol for heterogeneous wireless sensor networks

Sensor nodes in a network consume energy in a non-uniform manner. Designing clustering protocols that are heterogeneity aware is still an open issue in sensor networks. This work focuses on hierarchically clustered heterogeneous sensor networks. Sensor nodes organize themselves in self organized groups called clusters. Each cluster consists of a cluster head and some member nodes. The sensor network consists of nodes of two different energy levels. We show that current heterogeneity aware protocols (such as SEP [1], DEEC [2] etc.) are unable to distribute the usage of energy amongst the sensor nodes uniformly. We propose CRP, Cluster Re-election Protocol, that is heterogeneity aware and enhances the network stability period (period before which the first node dies) over current protocols. We show, by simulation, that CRP improves network stability by reducing the variation in the residual energy of sensor nodes. Therefore, CRP is able to exploit the heterogeneity present in a sensor network in an efficient manner.