Networked control systems under Denial-of-Service: Co-located vs. remote architectures

In this paper, we consider networked systems in the presence of Denial-of-Service (DoS) attacks, namely attacks that prevent transmissions over the communication network. Previous studies have shown that co-located architectures (control unit co-located with the actuators and networked sensor channel) can ensure a high level of robustness against DoS. However, co-location requires a wired or dedicated actuator channel, which could not meet flexibility and cost requirements. To overcome these limitations, we consider control architectures that approximate co-location while enable remote implementation (networked sensor and actuator channels). We analyze closed-loop stability and quantify the robustness “gap” between this architecture and the co-located one. The analysis framework is flexible enough to account for the case where control and sensor channels are shared as well as for the case where the two channels are independent and can be jammed at different time instants.