Date Added: Jan 2011
Sensor nodes are small battery powered devices which are deployed in large numbers to sense and collect information for various applications ranging from health care to military. Sensor networks need to rely on some cryptographic mechanism to communicate securely. Due to the resource constrained nature of sensor nodes, the symmetric key techniques are preferred over the public key ones. Key establishment using public key techniques has been used. In key pre-distribution, keys are preloaded in sensor nodes prior to deployment. After deployment, the sensors need to find if they share common key (shared-key discovery).