SEI Architecture Analysis Techniques and When to Use Them

The Software Engineering Institute (SEI) has developed two methods for analyzing system and software architectures—the Quality Attribute Workshop (QAW) and the Architecture Tradeoff Analysis Method (ATAM). These techniques, which are described in detail in various SEI technical reports and on the SEI Web site, can be used in combination to obtain early and continuous benefits. Designed to complement the ATAM, the QAW provides a method for analyzing a conceptual architecture or a system architecture against a number of critical quality attributes—such as availability, performance, security, interoperability, and modifiability—before the software architecture is fully developed. Once the software architecture is developed, the ATAM can be used to reveal how well the architecture satisfies particular quality attribute requirements and the risks, sensitivities, and tradeoffs involved in satisfying the requirements. The purpose of this technical note is to describe, using a hypothetical example, the alignment, combination, and uses of the two methods.