UAV Dynamic Service Function Chains Deployment Based on Security Considerations: A Reinforcement Learning Method

The efficient and secure management of resources within Flying Ad-Hoc Networks (FANETs) poses formidable challenges. FANETs constitute a pivotal element of the Space-Air-Ground-Integrated Network (SAGIN), employing Network Virtualization (NV) technology in tandem with Service Function Chain (SFC) to facilitate end-to-end network services, akin to terrestrial networks. Nonetheless, the transient, dynamic nature of FANETs coupled with their susceptibility to network attacks engenders considerable complexity in the placement of SFCs within these networks. To address the rationality and security of resource allocation for SFC placement, this paper proposes a reinforcement learning algorithm that sets strict security level restrictions on the placement process and fully extracts the key features in FANETs. Additionally, a multi-layer policy network is devised to dynamically perceive alterations in the FANET environment and compute an optimal SFC placement strategy. The proposed algorithm exhibits real-time adaptability to the dynamic environment, quantifies influential factors during placement, and achieves dynamic SFC placement. To assess the efficacy of the algorithm, three evaluation metrics—namely, SFC placement success rate, long-term average revenue, and long-term revenue cost ratio—are formulated and extensively evaluated through a plethora of experiments. Comparative analysis against alternative algorithms demonstrates enhancements of 20.6%, 15.3% and 12.1% in the aforementioned metrics, respectively. The experimental findings substantiate both the convergence and efficiency of the proposed algorithm.