Quality-driven architecture design and quality analysis method A revolutionary initiation approach to a product line architecture

The role of software architecture has changed. The use of modern software technologies and practices enables turning the focus of system development to the quality aspects of software instead of functional properties. Architecture addresses the quality issues of software and, therefore, it must be developed and documented properly. In particular, there is a need for high level architectural descriptions. The top down nature of software architecture design induces this need. In this report we introduce a quality-driven architecture design and analysis (QADA) method. Quality-driven is about utilizing architectural styles and patterns as a means of designing high-quality architectures. QADA takes a revolutionary approach to the initiation process of a new product line. That is, the development of a complete product-line architecture and a set of components before developing the first product in a new domain. QADA considers architecture on two levels of abstraction: conceptual and concrete. Design produces architectural descriptions at both abstraction levels from three viewpoints: structural, behavior and deployment. The structural viewpoint is concerned with composition of software components, whereas the behavior viewpoint takes the behavioral architecture aspects under consideration. The deployment viewpoint refers to embedding and allocation of software components to various computing environments. Quality of architecture on both levels of abstraction is analyzed in the corresponding analysis phases. Because software architectural design is difficult to discuss merely at an abstract level, the QADA method is tested with a case study of a distributed service platform. The platform embodies a layered service architecture, thereby providing a variety of services for its users. The upper layer of services, i.e. the system services of the platform is mobile, enabling spontaneous networking.