END-TO-END DESIGN OF DISTRIBUTED REAL-TIME SYSTEMS

This paper presents a systematic approach to the design of distributed real-time systems with system-level timing requirements. It is often extremely difficult to design such a system in a composable fashion, s ince temporal relationships induced by system-level timing requirement s introduce complicated couplings between structurally irrelevant comp onents. As a solution to this problem, the approach described here map s system-level timing requirements onto component-level timing constra ints. More specifically, it first transforms system-level requirements into a set of non-linear intermediate constraints; and then derives t ask attributes such as periods, phases, and deadlines, with the object ive of maximizing the chances of the system being schedulable. The fin al results preserve the desired timing correctness: if the final task set is schedulable, then the original system-level requirements will b e satisfied. The approach is demonstrated and experimentally validated via an example of a numerical control system built on the FIP network . (C) 1998 Elsevier Science Ltd. All rights reserved.