Software Architecture: Foundations, Theory, and Practice

Chapter 6. Modeling

As we have stated, every software system has an architecture, whether it is a "good" architecture or not. We have previously defined architecture as the set of principal design decisions about a system. Once design decisions have been made, they can be recorded. Design decisions are captured in models; the process of creating models is called modeling. From Chapter 3 we have:

Definitions. An architectural model is an artifact that captures some or all of the design decisions that comprise a system's architecture. Architectural modeling is the reification and documentation of those design decisions.

Models can capture architectural design decisions with varying levels of rigor and formality. They enable users to communicate about, visualize, evaluate, and evolve an architecture. Without models, architectures are inscrutable.

Throughout the chapter, we also discuss how architecture modeling notations are used to capture design decisions.

Definition. An architectural modeling notation is a language or means of capturing design decisions.

Available architecture modeling notations range from the rich and ambiguous (such as natural language) to the semantically narrow and highly formal (such as the Rapide architecture description language). While some models conform to a single notation, a model may also use a mix of different notations. For example, a single model may use the Unified Modeling Language (UML) class diagram notation to describe the classes in a system, but ...