ABSTRACT. This paper presents a novel, scenario-based notation called Use Case Maps (UCMs) for describing, in a high-level way, how the organizational structure of a complex system and the emergent behavior of the system are intertwined. The notation is not a behavior specification technique in the ordinary sense, but a notation for helping a person to visualize, think about, and explain the big picture. UCMs are presented as “architectural entities” that help a person stand back from the details during all phases of system development. The notation has been thoroughly exercised on systems of industrial scale and complexity and the distilled essence of what has been found to work in practice is summarized in this paper. Examples are presented that confront difficult complex-system issues directly: decentralized control, concurrency, failure, diversity, elusiveness and fluidity of runtime views of software, self modification of system makeup, difficulty of seeing large-scale units o...
Raymond J. A. Buhr