The Spring Architecture

Next generation, critical, hard real{time systems will require greater exibility, dependability, and predictability than is commonly found in today's systems. These future systems include the space station, integrated vision/robotics/AI systems, collections of humans/robots coordinating to achieve common objectives (usually in hazardous environments such as undersea exploration or chemical plants), and various command and control applications. Our research approach challenges several basic assumptions upon which most current real{time systems are built and subsequently advocates a new paradigm based on the notion of predictability and on a method for on{line dynamic guarantee of certain types of deadlines. The new paradigm requires an integrated set of solutions spanning from design and speci cation methods and tools, to real-time languages, to real-time operating systems, and to real-time architectures. The primary purpose of this paper is to provide an overview of the major ideas of this new paradigm and to explain the rami cations of this paradigm for the architecture.