An Efficient Authenticated Group Key Agreement Protocol for Dynamic UAV Fleets in Untrusted Environments

Unmanned aerial vehicle (UAV) fleets are the focus of various nations nowadays. Thus, it is expected to witness an explosion of reliability and safety critical UAV-based applications. Moreover, the recent surge of research on applied artificial intelligence and the industry advancement encourage the use of cooperative UAV fleets that offer potential collaborations even between UAVs from different organizations. The untrusted nature of the operation environments in addition to the high level of criticality of such applications require stringent secure protocols. There have been several security protocol proposals to ensure authentication, confidentiality and integrity, yet the overhead generated by these solutions and their impact on performance still severely hamper UAV endurance. In this paper, we propose to tackle the problem of secure communications within dynamic UAV fleets in open public networks using a pairing free Certificateless-Authenticated Group Key Agreement (CL-AGKA) scheme with constant rounds that meets efficiency and strong security. The formal security validation of the proposed protocol has been done by using Automated Validation of Internet Security Protocols and Applications tool (AVISPA). The aforementioned tool revealed that the proposed protocol is resilient against several attacks. More important, the computation cost has been significantly reduced thanks to the elimination of the expensive pairing operations and to the integration of the signature scheme into the key agreement to build one efficient algorithm.