Research On CPK-based Key Management Scheme In Wireless Sensor Networks

In recent years, the rapid development and wide application of WSN(Wireless Sensor Networks) in various fields of the society, makes it a research hotspot at home and abroad. Wireless sensor network is an open network, which is often deployed to the harsh environment. It is easy to suffer from various types of network attacks. The sensor nodes can easily be captured or tampered. Ensuring network security is a prerequisite for wireless sensor networks to play its role. Therefore, it’s necessary to design a secure and efficient key management scheme for WSN to establish session keys between sensor nodes. Generally, in order to save cost and control the node size, nodes in sensor networks typically have characteristics of limited battery energy, weak storage capacity, low communication bandwidth and limited computing ability. These features give more difficulty to the design of key management scheme in WSN which requires not only less complexity and fewer resources consumption, but also be able to ensure the safety and reliability of the network. Therefore, traditional key management mechanism cannot be applied to WSN directly. In consideration of these features of sensor nodes, a Combined Public Key based key management scheme for wireless sensor networks is proposed in this paper based on the complexity of solving elliptic curve discrete logarithm problem. And we also introduce the network model of the program, initialization before the network deployment, process of key agreement and key update, and network dynamic expansion in detail. In this paper, a large number of keys generated by the combination of little matrix elements alleviate the contradiction between the limited storage space and the large storage requirements of keys greatly. Analysis and comparison result show that the program has strong safety, it can resist collusion attacks, message replay attacks, denial of service attacks and other common attacks in WSN, and have a greater advantage in network connectivity rate, storage efficiency, network traffic, computational overhead and other aspects, compared with the traditional of the programs. It can be applied to large distributed wireless sensor networks.