The Research On Group Key Management In Wireless Sensor Networks

Sensor network is composed of lots of sensor nodes, which work together for acquiring, processing information. Meanwhile, sensor network is resource-limited. Such limitations include computation ability, memory capability, power limitation and communication bandwidth & range. Many emerging wireless applications for emergency and military situations depend upon secure group communications. But group key management in sensor networks faces a great challenge because of the resource-limited. This thesis mainly focuses on the group key management in sensor networks.This thesis firstly analyzes and compares some group key management in sensor networks. With the standpoint of improving the security of group key management scheme, decreasing the memory and communication overheads when group rekeying, the thesis presents a distributed group key management scheme based on threshold secret sharing mechanism and group key share update mechanism, in which only innocent node can have an efficient share of group key. When group rekeying, each node collaborates with some neighbour nodes to get the new group key. Meanwhile, introduces a group key share update mechanism to prevent conspiracy attack from promised nodes. Theoretical analysis and simulation results show that the distributed group key management scheme has lower memory and communication overheads besides good security performance compared to the old schemes. But, in this scheme, each node does the same operation when group rekeying, its computer and communication are big. To solve the shortcomings in the distributed scheme, based on clustering in sensor networks, the thesis presents a cluster-based group key management scheme. Compared to the distributed scheme, the new group key is only generated by cluster head and will be distributed to the nodes in cluster securely. Theoretical analysis and simulation results show that the cluster-based scheme has the same security with the distributed scheme, decreases the computer & communication overheads and solves the isolated node problem in distributed scheme.