  Recent work in the area of interdependent networks has focused on
interactions between two systems of the same type. However, an important and
ubiquitous class of systems are those involving monitoring and control, an
example of interdependence between processes that are very different. In this
Article, we introduce a framework for modelling distributed supervisory control
in the guise of an electrical network supervised by a distributed system of
control devices. The system is characterised by degrees of freedom salient to
real-world systems--- namely, the number of control devices, their inherent
reliability, and the topology of the control network. Surprisingly, the
behavior of the system depends crucially on the reliability of control devices.
When devices are completely reliable, cascade sizes are percolation controlled;
the number of devices being the relevant parameter. For unreliable devices, the
topology of the control network is important and can dramatically reduce the
resilience of the system.
