A self-managing volatile key scheme for wireless sensor networks

The last decade has seen major advances in Wireless Sensor Networks (WSN). The limited amount of resources in WSNs is the main challenge for securing them. Indeed, sensors are inherently small devices with limited embedded storage, processor and battery capacity. The situation is even worse when attackers, with virtually unlimited amount of resources, have direct physical access to sensors. Cryptographic keys are used for authentication, authorization, confidentiality, data integrity, as well as many other security services. Several proposals have been made for key management in WSNs. In this paper, we review some notable key management schemes and propose a new one. The originality of our work lies in two main facts: first, we do not place a master key on all sensors before deploying them as several other proposals did, but we rather place the master key in a subset of sensors; second, the master keys are volatile, i.e., sensors use the master key to bootstrap the system and they delete them shortly after that. Our extensive simulations have shown the efficiency of our approach.