Key Management in Wireless Sensor Networks

Establishing pairwise symmetric keys is a critical resource management issue in wireless sensor networks. Usually deployed in a hostile environment where malicious users or adversaries are bound to exist, wireless sensors are subject to a general attack model—a sensor node can be captured, re-programmed, and consequently exhibit arbitrary faulty behaviors. Thus, sensor key management is a challenging research issue, attracting a high level of interests in recent years. In general, a key management system works by first pre-allocating some keys to each sensor before deployment. After deployment, neighboring sensors can undergo a discovery process to set up shared keys for secure communications. An efficient key management scheme has to work under severe system constraints including limited memory storage and communication overhead in each sensor. In this chapter we provide a detailed survey of state-of-the-art sensor key management techniques that have demonstrated a high degree of effectiveness.