Designing in a Logical/Functional Viewpoint

Abstract

This chapter describes the next phase of the MBSAP process, showing how the top-level architecture from the Operational Viewpoint (OV) is transformed into a functional design of the system in a Logical/Functional Viewpoint (LV). We familiarize the reader with the concepts and techniques involved in carrying the five Perspectives of the OV to the level of a functional architecture, using the E-X example for illustration. We discuss design patterns, making the point that although these arose in the world of software, they have great applicability and payoff when applied to entire systems. For example, we show how Domains are decomposed to the level of actual system components, modeled as Blocks. Similarly, we will take the representation of system behaviors down to individual Blocks or groups of Blocks and begin to look at the timing of system functions. In the Data Perspective, we illustrate the use of Inheritance to specialize Foundation Classes from the Conceptual Data Model into actual system data entities in a Logical Data Model. We introduce the key subject of layered architectures that are organized on the basis of services to create a computing platform on which applications software and user interfaces can be hosted. Next, we show what the LV looks like in the Smart Microgrid. When the LV is complete and fully documented, the system architect can furnish a set of functional specifications and other architecture artifacts to hardware and software developers, procurement and material management specialists, and others to use in implementing, integrating, testing, producing, and sustaining the system. We end the chapter with a discussion of executable architectures and a summary of key points in the LV. Chapter objective: the reader will be able to transform the high-level architecture of an OV into a functional design in an LV with supporting implementation documentation.