Behaviour based Trust Management using geometric mean approach for Wireless Sensor Networks

The resource constraints of Wireless Sensor Network (WSN) make it easy to attack and hard to protect. Although carefully designed cryptography and authentication help to make WSN securer, they are not good at dealing withcompromised node and ageing node, whose misbehavior may impair the function of WSN. Hence, they are not sufficient for secure routing of message from source to destination in WSNs.Alternatively Trust management schemes provide a powerful tool for the detection of unexpected node behaviours. A solution is obtained by first figuring out the malicious nodes in the network and then separating them from the benevolent nodes present on the basis of trust levels assigned. In this paper, we propose a new Trust Management System by considering the behaviours of sensor nodes, direct and indirect trusts based on Geometric Mean (GM) of the QoS characteristics (trust metrics) among the nodes, which allows for trusted nodes only to participate in routing messages.