An Authentication Key Establish Protocol for WSNs Based on Combined Key

Advances in lattice-based cryptography are enabling the use of public key algorithms (PKAs) in power-constrained ad hoc and sensor network devices. Unfortunately, while many wireless networks are dominated by group communications, PKAs are inherently unicast—i.e., public/private key pairs are generated by data destinations. To fully realize public key cryptography in these networks, lightweight PKAs should be augmented with energy efficient mechanisms for group key agreement. Recently, many key management schemes for the WSNs have been proposed, but the computation and communication costs of these protocols are too high to suitable for WSNs. This paper proposes a key establish protocol for the WSNs based on combined key. The protocol adopts seed key mapping technology to achieve two-party and multi-party key establish in the WSNs, it can generate a large number of combination keys with little resources. So it effectively solve the contradiction between the sensor nodes need large storage space to store shared key with their neighbors and their limited storage space. It can also achieve mutual authentication between nodes when they establish shared key. Analysis shows that the proposed protocol has the advantages in storage efficiency, computation consumption and Communication consumption and suitable for wireless networks.