Distinguishable attack and fault detection in Interconnected cyber-physical systems

This paper delves into the intricate challenge of discerning anomalies within interconnected cyber-physical systems (ICPSs), especially when confronted with intertwined faults and cyber attacks. At the outset, the cyber attack detection capability of the unknown input observer (UIO) is improved with the combination of the neighboring state augmentation and redundancy detection techniques. This is followed by the design of a Luenberger observer(LO)-based fault detection strategy that integrates both the physical-interlinked information with neighbors and the local output collections, thus ensuring robust fault detection performance, even amidst attacks. Expanding on this, residual-based distinguishable attack and fault detection metrics are devised and the interoperability of the dual UIO and LO guarantees the simultaneous differentiation of interleaved-action faults and cyber attacks. Concluding the discourse, the results from case study in ICPSs validate the efficacy of the proposed strategy for detection, which utilizes a dual observer-based approach for distinct identification.