On the Formal Verification of a Cluster Based Key Management Protocol for Wireless Sensor Networks

Security is a primary problem in wireless electronic communications. However, the limitations of Wireless Sensor Networks (small size, low battery capacity and exposed communication media) often turn the focus to power consumption rather than security. However, insufficient security protection can leave a WSN application open to attack, rendering the supplied service not trustworthy or unavailable. This paper presents a formal verification of a cluster based key management protocol for Wireless Sensor Networks. A number of weaknesses are identified in the verified protocol that can be exploited by an intruder. These weaknesses allow various attacks, such as impersonating the base station to the network, impersonating a cluster head to sensor nodes or to disrupt the network configuration. A detailed discussion on these weaknesses is presented and modifications to the protocol are proposed to fix these weaknesses. Successful verification of the proposed fixed protocol demonstrates its correctness.