32.6. Summary of Themes in Architectural Analysis

One theme to note is that “architectural” concerns are especially related to non-functional requirements, and include an awareness of the business or market context of the application. At the same time, the functional requirements (for example, processing sales) cannot be ignored; they provide the context within which these concerns must be resolved. Further, identification of their variability is architecturally significant.

A second theme is that architectural concerns involve system-level, large-scale, and broad problems whose resolution usually involves large-scale or fundamental design decisions; for example, the choice of—or even use of—an application server.

A third theme in architectural analysis is interdependencies and trade-offs. For example, improved security may affect performance or usability, and most choices affect cost.

A fourth theme in architecture analysis is the generation and evaluation of alternative solutions. A skilled architect can offer design solutions that involve building new software, and also suggest solutions (or partial solutions) using commercial or publicly available software and hardware. For example, recovery in a remote server of the NextGen POS can be achieved through designing and programming “watchdog” processes, or perhaps through clustering, replication, and failover services offered by some operating system and hardware components. Good architects know third-party hardware and software products.

The opening definition of architectural concerns provides the framework for how to think about the subject of architecture: identifying the issues with large-scale or system-level implications, and resolving them.