  Unmanned Aerial Vehicle (UAV) networking is increasingly used in field
environments such as power inspection, agricultural plant protection, and
emergency rescue. To guarantee UAV networking security, UAV identity
authentication attracts wide attention, especially in the field environment
without perfect infrastructure. Some blockchain-based UAV identity
authentication solutions are proposed to establish decentralized and trusted
authentication systems without relying on infrastructure. However, these
solutions do not support disconnected UAV reconnection or even disband a
cluster directly after its head UAV disconnection, which compromises cluster
robustness and task result integrity. In this paper, we propose a
blockchain-based identity authentication solution oriented to multi-cluster UAV
networking with a UAV disconnection mechanism and a task result backup
mechanism. Specifically, we build a blockchain maintained by head UAVs of all
clusters, managing identity information to guarantee the security of
decentralized identity management. The UAV disconnection mechanism permits a
verified distributed UAV reconnection to ensure the robustness of the UAV
cluster, and on this basis, the task result backup mechanism ensures the
integrity of the task results stored in a cluster even any UAV disconnection.
Finally, extensive experimental results prove the superiority of our solutions
in terms of robustness, integrity, delay, and energy consumption.
