Modular design of multicomputer systems

Abstract

Multicomputer systems involve complex hardware and software components with extensive interactions. Furthermore, rapid advances in semiconductor tech nology have resulted in many different ways to im plement a system requirement. The merits of different hardware implementations are difficult to determine at an early stage of design and will often change subsequently. Thus we need design methods that let us delay implementation deci sions as long as possible. The structure of a sys tem, i.e., the definition of major components and their interaction, is often independent of the physi cal implementation. The design of the structure, however, largely determines important system charac teristics such as performance, modularity, reliabil ity, visibility, and adaptability. We outline a design method based on guidelines that promote modularity and access graphs that specify interactions between components. This method is then applied to a typical example, the design of a network message processor. The processor handles communications in a network of multiple computers and interactive terminals.