An secure hierarchical key agreement scheme for wireless sensor networks

In Wireless Sensor Networks (WSN), a key agreement scheme is an essential task for secure communications. Recently, Lee and Kim proposed a hierarchical key agreement scheme for the fresh key establishment in WSN. This scheme achieves a secure session key agreement. In this paper, we analyze the security of the scheme and illustrate that their scheme is unconfident against the insider attack in practice. Moreover, it is also difficult to resist the replay attack in this scheme. Then, we proposed a novel scheme inspired by their scheme. The entities of our scheme include a Sink besides the sensor nodes, which interrupts the construction of the insider attack. Our scheme adopts the timestamp mechanism to resist replay attack, which could decrease the storing requirement of the sensor nodes. Thus, it is more practical and realistic. We illustrate that our proposal can provide stronger security than Lee and Kim’s scheme.