A delay density model for networked control systems

In networked control systems, a physical process interacts with digital computation and networks. Such systems are often called cyber-physical systems. To ensure a safe and reliable operation of such systems, timing aspects must be considered in the design process. This work introduces the delay density, a new delay model that links the timing requirements of the functional system with the underlying platform architecture. Thereby, the delay density describes the maximum and minimum cumulative delay in an interval of events. The delay density allows to specify the timing requirements in an expressive way and on the other hand defines guaranteed delay bounds. We show in this paper how to derive the delay specification from a control system and how to use real-time analysis methods to verify the delays.