Threats and Security using Trust Techniques in Wireless Sensor Networks

Wireless Sensor Networks are implementing on large scale in real time environments due to its incredible uses in real life. Wireless Sensor Networks don’t need human interference for its working so they can place where human cannot reach easily. As sensor nodes are placed in an open and insecure environment, they are prone to security attacks by adversaries. So, the security is an impo rtant issue in sensor networks. Traditional security mechanisms like cryptography, intruder detection, routing protocols were implemented to provide security in wireless sensor networks. These mechanisms are capable to detect and remove internal attacks but fail to detect compromised nodes in a network. Compromised node exposes all secrets of network to the adversary which in turn put all existing mechanisms at risk. To overcome this problem various trust and reputation mechanisms have been proposed. Trust can be calculated in two ways. First, it can directly calculate with the past behavior of nodes. Secondly, it can be indirectly combined with the reputation of a node from the recommenders. Recommenders are neighbors of a node. In this paper, various security threats to the network, traditional security techniques, and various reputation and trust mechanisms h ave been discussed. Keyword: Wireless Sensor Networks, Sensor Node, Network Attacks, Security Mechanisms, Reputation, Trust.