面向无人机群组的轻量动态密钥管理方案

针对无人机群组在军事对抗复杂环境中，网络拓扑结构动态变化，提出了一种面向无人机群组的轻量动态密钥管理方案，旨在解决无人机加入及退出、批量加入及退出、群组合并及分裂等网络拓扑动态变化导致密钥更新问题，同时在网络拓扑没有变化情况下进行本地周期性更新，提高无人机群组密钥更新效率。将参与构造的秘密信息分为用户空间、剩余空间和撤销空间，用户空间可以在接收密钥组管理器（key group manager，KGM）的广播消息后，计算恢复出会话组密钥，剩余空间和撤销空间无法计算恢复出组密钥。密钥更新过程中，KGM利用空闲时间提前在密钥池中选取密钥进行预计算处理，降低KGM因构造广播消息进行复杂计算导致的时延问题。分析和实验仿真表明，该方案具有前向和后向安全性、抗共谋攻击和节点撤销能力，与现有无人机密钥管理方案相比，该方案优化了计算和通信开销，且节点存储开销较小，适用于动态拓扑变化的无人机群组网络。

Lightweight dynamic key management scheme for UAV group

Aiming at the dynamic changes of network topology of UAV group in the complex environment of military confrontation. This paper proposed a lightweight dynamic key management scheme for UAV group, which solved the key update problems when the network topology changed dynamically, such as UAV joining and exiting, batch joining and exiting, group merging and splitting. When the network topology didn''t change, the scheme could also provide local periodic key update, to improve the efficiency of UAV group key update. By constructing a congruent system, the scheme divided the secret information into user space, free space and retract space, the user space could calculate and recover the session group key after receiving the broadcast message from KGM, but the free space and retract space couldn''t calculate and recover the group key. During the key update process, KGM used idle time to select the key from the key pool in advance for predictive calculation, which reduced the delay caused by constructing broadcast messages for complex calculation. Through analysis and experiments, the scheme has forward and backward security, anti-collusion attack and node cancellation capabilities. Compared with existing UAV key management schemes, the scheme optimizes the computation and communication overhead, and the node storage overhead is small, which is suitable for the UAV group network with dynamic topological changes.