Abstract
Wireless Sensor Network (WSN) is a large network of sensor nodes, which operates in low power and capable of transmitting to a shorter distance with low bandwidth. It comprises of sensing unit, processing unit, memory unit, power supply and transceiver. As these sensor nodes are battery operated, the lifetime of the sensor node depends on the life of the battery. The sensor nodes in the network communicate in a mesh and multi-hop fashion, redundant data may exist in the network. In order to enhance the robustness and accuracy of the information obtained by the network, redundancy has to be reduced. One such protocol which works on the basis of data fusion to reduce redundant data is LEACH (Low Energy Adaptive Clustering Hierarchy). The LEACH protocol uses limited energy thus increases the network lifetime. The security of information transfer via wireless network is a challenging issue. In order to check the reliable operation of LEACH routing protocol, we implemented gray hole attack and evaluated the performance of the LEACH protocol in terms of metrics like packet drop ratio, throughput and Average End-to-End delay. The evaluation of LEACH with Gray hole attack has been done with the help of Ns2 simulator.