An object communication architecture for real time distributed process control

Abstract

We consider the automation and supervision software applications that are the first levels of the Computer Integrated Manufacturing hierarchy. We define that the application requires time properties (a bounded time exchange and/or a time validity) and ordering properties (a causal and total order). We explain the interest and the difficulties to get these two properties in an asynchronous context. Our communication architecture is composed of three asynchronous systems. A field bus provides mainly time properties for the automation. A client-server system allows exchanges between the automation and the supervision. The multicast memory system provides order and time validity properties for both the supervision and the automation.