4. Architectural Quality Attributes

AWS WAFAzure WAFGCP WAF

Purpose

Architectural Quality Attributes are cross-cutting quality checks — evaluated across all views rather than within a single view. They are derived from the Well-Architected Frameworks published by AWS, Azure, GCP, Oracle, and IBM, unified into quality attributes that address the key architectural concerns of any solution.

Unlike the Architectural Views (Section 3), which describe what the solution is, Quality Attributes evaluate how well it is designed.

Quality Attributes

#	Quality Attribute	Focus
4.1	Operational Excellence	Observability, monitoring, operational procedures
4.2	Reliability & Resilience	DR, scalability, fault tolerance, backup/recovery
4.3	Performance Efficiency	Performance requirements, resource optimisation
4.4	Cost Optimisation	Cost analysis, FinOps, cost-effective design
4.5	Sustainability	Energy, carbon, resource efficiency

These quality attributes are derived from the Well-Architected Frameworks published by AWS, Azure, GCP, Oracle, and IBM. For the full provider-by-provider mapping, see the Framework Alignment page.

Security as a View, Not Just a Quality Attribute

In the cloud Well-Architected Frameworks, Security is a quality attribute (pillar). In this standard, Security is elevated to a full Architectural View (Section 3.5) because of the depth of documentation required for IAM, encryption, network security, and monitoring. The Security View directly covers the security concerns that cloud providers treat as a quality pillar — so there is no separate security score in the quality attributes table.

How to Use Quality Attributes

1. Design Phase — Use each quality attribute’s guidance to inform design decisions
2. Review Phase — Evaluate the completed design against each quality attribute
3. Tradeoff Documentation — Where quality attribute requirements conflict (e.g., cost vs. resilience), document the tradeoff and the rationale for the chosen balance
4. Cross-Reference — Reference specific quality attribute concerns within the Architectural Views using the quality attribute callout format (the coloured cross-reference boxes at the bottom of each view page)

Quality Attribute Tradeoffs

Optimising for one quality attribute may come at the expense of another. Key tradeoffs to consider:

Tradeoff	Description
Reliability vs. Cost	Higher availability requires redundant infrastructure
Performance vs. Cost	Better performance may require more powerful (expensive) resources
Security vs. Usability	Stronger security controls may increase friction for users
Sustainability vs. Performance	Energy-efficient choices may not be the highest-performing
Reliability vs. Sustainability	DR environments and redundancy consume additional resources

Document any significant tradeoffs in Section 3.6 (Scenarios / ADRs).