A Metric for Quantifying Key Exposure Vulnerability in Wireless Sensor Networks

Wireless sensor networks are often used in applications where message confidentiality, integrity, and authentication are required. Cryptography is a common mechanism for meeting these security requirements. The use of cryptography requires that nodes share secret keys, which are typically assigned to each node according to key distribution schemes. Given a key distribution, there is currently no design metric for evaluating vulnerability to key exposure. In this work, we introduce a metric for analyzing and comparing the resilience of key distributions by introducing the concept of a Link Key Security Metric (LKSM). We define the properties needed in an LKSM and provide a metric that satisfies them.