One Model

One Model, Many Interests, Many Views

If a service function supports the transition, the name of the function is shown after the trigging event and call information. In addition, the nodes representing states optionally display entry (what functions occur when transitioning into the state), exit (what functions occur when transitioning out of the state), and do functions (the behavior that elaborates this state). The ability to effectively read a state transition diagram corresponds more to an individual’s mental model than their role or background. That said, systems and software engineers are classically trained to understand state transition diagrams. For that reason, the view is an effective representation when taking a higher-level, orthogonal look at the behavior of the system. Representing the System Implementation Much as Jim Long noted that the various systems engineering diagrams of behavior could be plotted along a spectrum representing the degree of data and structural content, diagrams representing the physical architecture can be plotted in two dimensions. The first dimension (the X axis) parallels Jim’s concepts of a behavioral spectrum in the physical architecture domain. The spectrum reflects the two key physical characteristics of composition (the parts tree of a system) and connectivity (how those parts are interconnected externally and internally). The second dimension is the level of detail moving from representations best suited for system architecting and diverse audiences at level 0 and level 1 of the system architecture to representations better suited for design and technical audiences at level N of the architecture.

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