Wireless Sensor Networks are often deployed in adverse or hostile environments so there is always a need for key management schemes for sensor nodes. The existing q-composite Random Key Predistribution (RKP) scheme is a probabilistic key management scheme where each node is preloaded with a subset of keys that are randomly selected from a pool of keys. If a pair of neighbor nodes which have at least q common keys can be used to establish a secure link between the nodes. In this paper, we enhanced the previous security analysis (i. e. , resilience against node capture) of the q-composite RKP scheme and we present a lightweight implementation of the Elliptic Curve Diffie-Hellman (ECDH) key exchange for wireless sensor nodes Elliptic Curve Diffie-Hellman (ECDH) key exchange which is feasible for resource-restricted sensor nodes. The proposed method ECDH key exchange in WSNs is offering perfect resilience to node capture, excellent scalability, and low memory as well as reducing communication over-head. ECDH is the highly computation-intensive nature of its underlying cryptographic operations, causing fast execution times and with low energy consumption. Our results show that a full ECDH key exchange between two different nodes consumes a normal energy (including radio communication), which is significantly better for high secure environment reported ECDH implementations on comparable platforms.

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Wireless Sensor Network Security Key Management Random Key Pre-distribution Resilience