The technological advances in wireless communication systems and digital data processing techniques has given rise to many innovative intelligent networks. One such network is wireless sensor network (WSN). In recent past, huge growth has been perceived in the applications of WSN. In wireless sensor network, the battery powered sensor nodes are scattered in a monitoring area and it is impossible to replace the batteries of sensor nodes after deployment. Therefore, energy efficiency remains a prime concern in design of WSNs. The routing protocols help to find energy efficient routes and increases the lifetime of WSNs. The cluster-based routing techniques play an important role in design of energy efficient WSNs. However, authors analyzed two types of sensor networks in the literature such as homogeneous and heterogeneous networks. In homogeneous clustering, all sensor nodes possess same level of initial energy and cluster head (CH) formation probability of each node in such networks remains equal. In heterogeneous clustering, the nodes are bifurcated into three energy levels such as normal node, advanced node and super node. Therefore, the CH formation probability of a node in such network depends on the type of node. This paper presented a survey on recent energy efficient routing protocols in homogeneous as well as heterogeneous wireless sensor networks. The energy efficient routing protocols are classified based on some quality of service (QoS) metrics such as energy efficiency, network lifetime, network stability, cluster head selection threshold and heterogeneity levels.
Hybrid Metaheuristic Aided Energy Efficient Cluster Head Selection in Wireless Sensor Network
