Security in the Wireless Sensor Network plays an important role and can be achieved by cryptographic algorithms. The cryptography is the science and art of transforming messages to make them secure and immune to attacks by authenticating the sender and receiver within the network. The Proposed methodology, hybrid cryptographic technique has combined Blowfish algorithm for symmetric and Elliptic Curve Diffie-Hellman algorithm for asymmetric. Blowfish algorithm provides high speed encryption process when compared with the other symmetric algorithms. The Elliptic Curve Diffie-Hellman algorithm combines the concept of elliptic curve and Diffie-Hellman key exchange algorithm. Hence, it provides more security compared to other asymmetric algorithm and the key exchange mechanism. Cluster based trust Management approaches are used to identify unauthorized user in WSN. It first identifies the trusted nodes in networks, then send packets through that trusted nodes. Trusted nodes are identified based on trust values to identify the neighboring nodes during verification process for improving the Packet Delivery Ratio and Energy Consumption.

Sensor node, Elliptic Curve, Blowfish, Diffie-Hellman, Trust Node Calculation, WSN

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