How do you define and measure the key architecture quality attributes in TOGAF?

1 Quality attributes

Quality attributes are the non-functional characteristics of an architecture that affect its performance, usability, security, reliability, and maintainability. Examples of quality attributes are availability, scalability, interoperability, modularity, and testability. Quality attributes are often derived from the stakeholder concerns and the business drivers of the architecture. TOGAF suggests using a quality attribute scenario to define and document a quality attribute. A quality attribute scenario consists of six parts: source, stimulus, artifact, environment, response, and response measure. For example, a quality attribute scenario for availability could be:

Source: A user

Stimulus: Requests a service

Artifact: A system component

Environment: Normal operation

Response: The service is delivered

Response measure: Within a specified time

2 Quality assessment

Quality assessment is the process of evaluating how well an architecture satisfies the quality attributes. TOGAF recommends using a combination of quantitative and qualitative methods for quality assessment. Quantitative methods involve measuring the actual or expected performance of the architecture against the response measures defined in the quality attribute scenarios, while qualitative methods involve reviewing the architecture against best practices, principles, standards, and guidelines. TOGAF provides several tools and techniques for quality assessment, such as an architecture compliance review to check alignment with enterprise architecture standards and policies, an architecture maturity assessment to measure maturity level based on a predefined model or framework, an architecture capability assessment to measure an organization's capability to deliver and manage an architecture based on a predefined model or framework, and an architecture trade-off analysis to compare and balance trade-offs between different quality attributes and design alternatives.

3 Quality improvement

Quality improvement is the process of identifying and implementing actions to enhance the quality of an architecture. TOGAF suggests using a continuous improvement cycle to monitor and improve the quality attributes throughout the architecture lifecycle. The cycle consists of four steps: plan, do, check, and act. In the plan step, the quality objectives, criteria, and metrics are defined and agreed. In the do step, the quality activities, tasks, and responsibilities are executed and documented. In the check step, the quality outcomes, results, and feedback are collected and analyzed. In the act step, the quality issues, gaps, and opportunities are addressed and resolved.

4 Quality communication

TOGAF emphasizes the importance of quality communication for ensuring the acceptance and adoption of the architecture. To facilitate this, TOGAF provides various tools and techniques, such as architecture views, viewpoints, models and documentation. Architecture views are a representation of a subset of the architecture that focuses on a specific quality attribute or concern. Architecture viewpoints specify the conventions and rules for creating and using an architecture view, while architecture models are a formal or informal description of an aspect of the architecture. Lastly, architecture documentation is a collection of artifacts that capture and convey the architecture information and decisions.

5 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?