Dynamic updating based key management algorithm for wireless sensor networks

In wireless sensor networks, sensor nodes are inherently restricted by insufficient hardware resources, such as computing capacity and battery lifetime. As a result, current key management schemes are difficult to be deployed in wireless sensor networks. This paper proposes a new key management method that the shared keys are dynamic updated for wireless sensor networks. The proposed scheme loads two hash functions and an initial key into the base station, cluster heads, and sensor nodes. Every node including the cluster heads and sensor node authenticates its neighbor nodes with the initial key. Then every node establishes pair wise key with each of its neighbor node to ensure transmission secrecy. The pair wise keys are updated between node and its neighbors within a random interval time, which is triggered by the base station. The security of this scheme is analyzed and it shows that it is robust to the guessing attacks, replay attacks, man-in-the-middle attacks and node capture attacks. The results show this scheme can also save communication resources.