Towards an Automated Approach for Early Architecture Tradeoff Analysis

While software architectures are an effective means for capturing stakeholder requirements and prescribing software system structure, the derivation of software architectures starting from requirements elicitations is a significant challenge. Specific challenges include (i) interpreting, modeling, and synthesizing requirements from a variety of stakeholders; (ii) transforming domain models into an architectural representation; (iii) transitioning the architecture from an initial, abstract representation to a more detailed, concrete representation; and (iv) evaluating the architecture against established high-level quality goals (e.g., reusability, testability, performance, comprehensibility) in a quantitative, systematic manner. This paper describes a tool, the Reference Architecture Representation Environment (RARE), designed to support derivation and tradeoff analysis of a domain-specific, implementation-independent reference architecture capturing domain requirements. This reference architecture is one in a series of interrelated architectures (e.g., application architecture, implementation architecture) designed to capture various levels of stakeholder concerns. RARE guides the architect through iterative refinement, evaluating the architecture after each iteration using quantitative metrics associated with quality goals. RARE provides features to handle traditional difficulties encountered during metric-based evaluation, including managing inherent conflicts between goals and correlating low-level metrics with high-level goals. The result is a domain reference architecture traceable to requirements and supported by the capture of derivation history and architect rationale.