Blockchain-Based Group Key Management Scheme In Hierarchical UAV Network

UAVs in multiple clusters in a hierarchical UAV network have complementary advantages,division of labor and cooperation,which have more advantages than single-machine operations,so it is widely used in agriculture,industry,traffic management and wireless communication.However,due to the inherent openness of UAV channels and the transmission of a large amount of private data when multiple UAVs perform tasks in these fields,communication in hierarchical UAV network faces many security issues.In this scenario,the group key is particularly significant as the first line of defense to ensure the secure communication within the UAV cluster,and the group key management mechanism,as a key technology to ensure the secure communication of the group,also plays a significant role in the hierarchical UAV network.However,most of the existing group key management mechanisms are either based on a key distribution center,which is easy to cause a single point of failure;or there is a problem that the entire group cannot be calculated and the group key can be updated in time when the group members are offline.In addition,when the topology changes frequently in the UAV network,it is inevitable to encounter the situation that multiple UAV nodes request key update at the same time.Therefore,designing a suitable group key management scheme for hierarchical UAV network should solve the above problems,and blockchain technology provides a feasible means for this.To this end,this paper firstly solves the single point of failure problem faced in group key management by utilizing the decentralized nature of blockchain.Then,under the premise of decentralization,two different key management schemes are designed to solve the problem that the group key can not be calculated and updated due to the group member’s offline,and the existing scheme can not handle the concurrent update of the key.The specific research contents are as follows:(1)A decentralized group key management scheme that supports asynchronous computation is proposed.Specifically,the scheme first adopts the group key calculation mechanism based on the asynchronous ratchet tree(ART)protocol,which realizes the early deployment of the group key by the cluster head UAV and when the cluster members are offline,the asynchronous calculation and autonomous update of the group key by other members.Then,the decentralization feature of blockchain is used to solve the single point of failure problem of most of the existing proposed group key management schemes,which improves the transparency and fairness of key management.Finally,the security analysis of the scheme is carried out,which proves that the scheme satisfies the forward and backward secrecy,and can effectively resist attacks such as camouflage and replay.The performance evaluation shows that compared with similar schemes,the cluster member UAV nodes in this scheme have lower communication overhead and lightweight energy consumption,and are suitable for application in a hierarchical UAV network environment.(2)A decentralized group key management scheme that supports concurrent update is proposed.Based on the system model of the previous scheme,this scheme firstly uses the Tree KEM protocol to calculate the group key,which realizes the concurrent update of the group key when multiple UAV nodes request to update.Secondly,using blockchain technology for key management can effectively avoid the single point of failure,and can realize the transaction traceability of key update.Most importantly,through the smart contract based on blockchain,the group dynamic change algorithm is designed,so that each node in the group can reliably interact.Finally,the security analysis shows that the proposed scheme can satisfy the forward and backward security,and can effectively resist various typical security threats such as message replay and camouflage attacks faced by the hierarchical UAV network.At the same time,the performance evaluation shows that,compared with the previous scheme and similar schemes,the ordinary UAV nodes in this scheme have lightweight energy consumption.