Key management in heterogeneous wireless sensor networks using Voronoi diagrams

Wireless sensor networks' nodes are divided to H-sensors and L-sensors. H-sensor nodes are more powerful than L-sensor nodes in term of processing and memory. Because of that H-sensors are considered as the cluster head and L-sensor as the cluster member. H-sensor is responsible for the security of this communication. Each node can communicate with neighbor nodes. Problems of the network are security and battery lifetime for each node. Proposed algorithm presents a scheme to keep the security, reduce energy consuming and the length of message in wireless sensor network. In this scheme each node select as a cluster head based on minimum distance of neighbor nodes. This algorithm, uses Voronoi algorithm, did the most optimal clustering and divides the operational environment to Voronoi spaces and allocate a key to each Voronoi space for secure connection with neighbor spaces. Each Voronoi spaces have special key, so that energy consuming decreases and security increases. This scheme is evaluated by MATLAB, simulation software, and compared with previous algorithms. Results of this simulation show that this scheme operates better than similar schemes because it decreases the length of message and energy consuming.