The Formative Years

RI is a rule-based program that configures VAX-I 1 computer systems. Given a customer’s purchase order, it determines what, if any, substitutions and additions have to be made to the order to make it consistent and complete and produces a numnber of diagrams showing the spatial and logical relationships among the 90 or so components that typically constitute a system. The program has been used on a regular basis by Digital Equipment Corporation’s manufacturing organization since January of 1980. Rl has sufficient knowledge of the configuration domain and of the pecularities of the various configuration constraints that at each step in the configuration process, it simply recognizes what to do; thus it requires little search in order to configure a computer system. The approach RI takes to the configuration task and the way its knowledge is represented has been described elsewhere [McDermott 80a, MC Dermott 80b]. This article provides a detailed description of Rl’s design and implementation history. As will become apparent, only a part of the effort to develop an expert configurer for Digital dealt in a direct way with AI issues. The other, and in fact larger, part involved providing the ever widening circle of individuals who came in