A decentralized energy-aware key management scheme for Wireless Sensor Networks

The popularity of Wireless Sensor Networks (WSNs) is increasing especially in applications where data needs to be remotely collected, such as in fire detection, health, or environmental monitoring. WSN nodes are limited in terms of processing capabilities and battery life. Thus, encryption is usually avoided and the readings are sent in the clear. This allows any eavesdropper to access data that could be confidential. Lightweight encryption techniques are proposed to overcome the limitations of sensor nodes. Identity-based encryption (IBE) that uses elliptic curve cryptography (ECC) seems to be very promising in terms of energy efficiency. Since the issue of key management is critical for a security system, we propose a novel decentralized IBE-based key management scheme that reduces the energy by using multiple base stations. The keys are pre-distributed in the WSN and refreshed at specific time intervals. The system ensures confidentiality of the messages and the availability of WSN service even when multiple nodes and base stations are compromised, at a significant reduction in overall system energy.