A Platform-Independent Component QoS Modeling Language for Distributed Real-time and Embedded Systems

Distributed Real-time and embedded (DRE) systems require multiple, simultaneous quality of service (QoS) properties, such as predictability, reliability and security for their correct operation. With increasing focus on composing DRE systems from components, it becomes necessary for system designers to ensure that the system composition and its QoS configurations are functionally and systemically compatible. Different dimensions of QoS, however, tend to conflict with each other requiring design-time QoS tradeoff analysis. This paper describes a model-driven engineering (MDE) approach to model and analyze the validity of the DRE system QoS properties. First, we describe the Component QoS Modeling Language (CQML), which enables visual separation of concerns in QoS modeling while internally maintaining a unified view of the system. Second, we illustrate how well-defined formalisms of system behavior defined in CQML can be leveraged to conduct QoS tradeoff analysis, such as Real-time schedulability analysis which is described.