CPSA Quality Attributes and Scenarios 5 — Questions and Answers
Question 1: Which technique is commonly used alongside quality scenarios to systematically evaluate how well an architecture meets quality goals?
- Entity-Relationship Modeling
- Architecture Trade-off Analysis Method (ATAM) (Correct answer)
- Unified Modeling Language (UML) class diagrams
- Test-Driven Development (TDD)
Correct answer: Architecture Trade-off Analysis Method (ATAM)
ATAM uses quality attribute scenarios as input to identify architectural risks, sensitivity points, and trade-offs in the proposed architecture.
Question 2: In a performance quality scenario, 'the system processes 1,000 transactions per second under peak load' is the:
- Stimulus
- Environment
- Response measure (Correct answer)
- Artifact
Correct answer: Response measure
The response measure is the quantifiable criterion that determines whether the system's response meets the quality goal.
Question 3: Which quality attribute is MOST relevant when a system must continue operating correctly even if one of its microservices fails?
- Portability
- Reliability — specifically fault tolerance (Correct answer)
- Usability
- Maintainability
Correct answer: Reliability — specifically fault tolerance
Fault tolerance, a sub-characteristic of Reliability, ensures the system continues to operate correctly despite component failures.
Question 4: The concept of 'sensitivity points' in ATAM refers to:
- Security vulnerabilities that need patching
- Architectural decisions that have a significant impact on one or more quality attributes (Correct answer)
- Requirements that are too sensitive to share with stakeholders
- Database columns storing personally identifiable information
Correct answer: Architectural decisions that have a significant impact on one or more quality attributes
Sensitivity points are architectural decisions where a small change significantly affects one or more quality attribute responses.
Question 5: Which quality attribute scenario would BEST help an architect decide between a monolithic and a microservices architecture?
- A security scenario about preventing SQL injection attacks
- A modifiability scenario where a single team must deploy a new feature independently without affecting other teams (Correct answer)
- A usability scenario about error messages shown to end users
- A portability scenario about running on Windows vs. Linux
Correct answer: A modifiability scenario where a single team must deploy a new feature independently without affecting other teams
Independent deployability and team autonomy are modifiability concerns that strongly favor a microservices architecture over a monolith.
Question 6: ISO 25010 replaces which older standard for software product quality characteristics?
- ISO 9001
- ISO/IEC 9126 (Correct answer)
- ISO 27001
- ISO 12207
Correct answer: ISO/IEC 9126
ISO/IEC 9126 was the predecessor to ISO 25010 (SQuaRE), which expanded and reorganized its quality model.
Question 7: A quality tree (or utility tree) in ATAM is used to:
- Model the system's class hierarchy for object-oriented design
- Organize and prioritize quality attribute scenarios from general utility down to concrete, measurable scenarios (Correct answer)
- Document the dependency graph between microservices
- Map user personas to functional requirements
Correct answer: Organize and prioritize quality attribute scenarios from general utility down to concrete, measurable scenarios
A quality/utility tree decomposes system utility into quality attributes, then into refined attribute concerns, and finally into specific concrete scenarios with business and technical priority ratings.
CPSA Quality Attributes and Scenarios 5
Which technique is commonly used alongside quality scenarios to systematically evaluate how well an architecture meets quality goals?