Real-Time Modelling of Distributed Component-Based Applications

This paper presents a modular modelling methodology to formulate the timing behaviour of real-time distributed component-based applications. It allows to build real-time models of the platform resources and software components, which are reusable and independent of the applications that use them. The proposed methodology satisfies the completeness, opacity and composability properties, required to ensure that the complete real-time model of an application, able to predict its temporal behaviour by schedulability analysis or simulation, may be assembled by composition of the real-time models of its constituent parts. These real-time models present a dual descriptor/instance based nature. A class of component, independent of any application, is modelled as a parameterized class-type descriptor, which describes its inherent temporal behaviour and includes references to the real-time models of other hardware/software modules that it requires. An instance of the component in a concrete application context is modelled by an instance-type model, which is generated by assigning concrete values to the parameters and unsolved references of its corresponding descriptor. Instances are formed and combined by automatic tools to build complete analysis models for each specific real-time situation