In Wireless Sensor Networks (WSNs), the traditional cryptographic mechanisms for security require higher consumption of resources such as large memory, high processing speed and communication bandwidth. Also, they cannot detect faulty, malicious and selfish nodes which lead to the breakdown of network during packet routing. Hence, cryptographic security mechanisms are not sufficient to select appropriate nodes among many neighbouring nodes for secure packet routing from source to sink. Alternatively, trust management schemes are tools to evaluate the trust of a node and thereby choosing a node for routing, and also detecting their unexpected node behaviour (either faulty or malicious). In this paper, we propose TENCR: a new Trust Evaluation method based on the Node’s QoS Characteristics (trust metrics) and neighbouring nodes' Recommendations. The proposed new technique detects the malicious and selfish nodes very efficiently than the arithmetic mean based methods, and allows trustworthy nodes in routing, thereby eliminating malicious/selfish nodes. Our proposed trust evaluation method is adaptive and energy efficient that separates the trustworthy nodes and qualify them to take the participation in routing, and disqualify the other nodes as malicious/selfish. Hence, trustworthy nodes only be allowed in routing, and malicious/selfish nodes will be eliminated automatically.
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