Reusable Component Analysis for Component-Based Embedded Real-Time Systems

Component-Based Software Engineering (CBSE) promises an improved ability to reuse software which would potentially decrease the development time while also improving the quality of the system, since the components are (re-)used by many. However, CBSE has not been as successful in the embedded systems domain as in the desktop domain, partly because requirements on embedded systems are stricter (e.g. requirements on safety, real-time and minimizing hardware resources). Moreover these requirements differ between industrial domains. Paradoxically, components should be context-unaware to be reusable at the same time as they should be context sensitive in order to be predictable and resource efficient. This seems to be a fundamental problem to overcome before the CBSE paradigm will be successful also in the embedded systems domain. Another problem is that some of the stricter requirements for embedded systems require certain analyses to be made, which may be very complicated and time-consuming for the system developer. This paper describes how one particular kind of analysis, of worst-case execution time, would fit into the CBSE development processes so that the component developer performs some analyses and presents the results in a form that is easily used for component and system verification during system development. This process model is not restricted to worst-case execution time analysis, but we believe other types of analyses could be performed in a similar way.