Resilient Leader–Follower Consensus of Fractional-Order Nonlinear Multi-Agent Systems Under Sybil and DoS Attacks via Event-Triggered Adaptive Control

This paper investigates the leader–follower consensus problem for fractional-order nonlinear multi-agent systems operating under simultaneous Sybil and Denial-of-Service (DoS) attacks. The communication topology is modeled as a time-varying directed graph with intermittent link failures due to DoS disruptions, while malicious data injection induced by Sybil attacks is incorporated into the agent dynamics. In addition, bounded disturbances and time-varying input delays are explicitly considered. To counter these challenges, an event-triggered distributed control framework was developed to reduce communication load while preserving agents’ tracking performance. Furthermore, an adaptive compensation mechanism is introduced to estimate and attenuate the combined effects of cyber attacks and external disturbances. A novel Wirtinger-type fractional integral inequality is established, providing a less conservative tool for constructing Lyapunov–Krasovskii functionals in fractional-order systems. Sufficient conditions for asymptotic leader–follower consensus are obtained in terms of linear matrix inequalities using fractional Lyapunov stability theory. The proposed scheme guarantees the convergence of tracking errors, excludes Zeno behavior through a decaying triggering threshold, and ensures robustness against malicious signal injection and communication interruptions. The results demonstrate that the developed event-triggered adaptive strategy achieves resilient consensus in fractional-order multi-agent systems despite simultaneous cyber attacks at both the network and information layers.