Experience with Global Analysis: A Practical Method for Analyzing Factors that Influence Software Architectures

A practical method for analyzing the factors that influence software architectures is presented. Factors include organizational context and constraints, available technologies, and product requirements. Analyzing the factors uncovers a small number of issues that drive the design of the architecture. These issues arise from the factors that have little flexibility, a high degree of changeability, and a global impact on the system. The result of the analysis is a set of global strategies that guide the architecture design. A two-phase approach for analyzing factors and developing architecture design strategies is given. Experience has been gained with this approach in three ways: (1) developing the approach during the design of an imaging system; (2) using the approach to analyze four systems in retrospect; (3) using the approach in new software development projects. Introducing global analysis into the software development process resulted in a new global analysis specification document that helped bridge the gap between requirements and architecture design and provided a place to explicitly record design rationale.