Vivekanand Jha, Elisha Chauhan, Harshpreet Kaur and Neeharika Taneja, Indira Gandhi Institute of Technology, India

A sensor network is composed of a large number of sensor nodes, which are densely deployed either inside the phenomenon or very close to it. Sensor nodes have sensing, processing and transmitting capability . They however have limited energy and measures need to be taken to make op- timum usage of their energy and save them from task of only receiving and transmitting data without processing. Various techniques for energy utilization optimisation have been proposed Ma jor players are however clustering and relay node placement. In the research related to relay node placement, it has been proposed to deploy some relay nodes such that the sensors can transmit the sensed data to a nearby relay node, which in turn delivers the data to the base stations. In general, the relay node placement problems aim to meet certain connectivity and/or survivabil- ity requirements of the network by deploying a minimum number of relay nodes. The other approach is grouping sensor nodes into clusters with each cluster having a cluster head (CH). The CH nodes aggregate the data and transmit them to the base station (BS). These two approaches has been widely adopted by the research community to satisfy the scala- bility objective and generally achieve high energy efficiency and prolong network lifetime in large-scale WSN environments and hence are discussed here along with single hop and multi hop characteristic of sensor node.

Clustering,Dominating Set,Relay Node,Sensor Node and Sink