CPSA Architectural Goals and Constraints 3 — Questions and Answers
Question 1: A hospital system requires 99.999% uptime for its patient monitoring module. Which architectural pattern most directly addresses this goal?
- Active-active redundancy with automatic failover (Correct answer)
- Microkernel architecture with pluggable modules
- Pipe-and-filter architecture for data processing
- Layered architecture with strict separation of concerns
Correct answer: Active-active redundancy with automatic failover
Active-active redundancy with automatic failover eliminates single points of failure, directly supporting extreme availability requirements like five-nines uptime.
Question 2: When a budget constraint limits the team to open-source middleware only, this is best classified as which type of constraint?
- Organizational constraint (Correct answer)
- Technical constraint
- Regulatory constraint
- Operational constraint
Correct answer: Organizational constraint
Budget limitations set by management or finance represent organizational constraints that restrict architectural choices to cost-appropriate technologies.
Question 3: Which approach is most appropriate when two critical quality goals appear mutually exclusive?
- Analyze scenarios to find a design point that acceptably balances both goals (Correct answer)
- Always prioritize security over all other quality attributes
- Choose the goal that satisfies the most stakeholders by count
- Defer the decision until the project is nearly complete
Correct answer: Analyze scenarios to find a design point that acceptably balances both goals
Scenario-based analysis helps architects find design solutions that achieve an acceptable balance rather than fully sacrificing either quality attribute.
Question 4: What role do business goals play in defining architectural constraints?
- Business goals translate into quality requirements that constrain architectural decisions (Correct answer)
- Business goals only affect marketing and have no impact on architecture
- Business goals define the database schema directly
- Business goals are irrelevant once the technical team starts design
Correct answer: Business goals translate into quality requirements that constrain architectural decisions
Business goals such as time-to-market, cost efficiency, or competitive differentiation translate into quality requirements that bound what architectural solutions are acceptable.
Question 5: A legacy mainframe integration requirement forces the use of COBOL-based batch interfaces. This exemplifies which constraint category?
- Technical constraint due to existing system dependencies (Correct answer)
- Regulatory constraint imposed by government mandate
- Organizational constraint from management preference
- Operational constraint from runtime environment limits
Correct answer: Technical constraint due to existing system dependencies
Existing system dependencies that force specific technology choices are technical constraints, as they arise from the current technology landscape rather than policy.
Question 6: How should an architect handle a constraint that is discovered to be based on a false assumption?
- Document the finding, validate with stakeholders, and renegotiate the constraint if the assumption is confirmed false (Correct answer)
- Ignore the constraint since it was based on incorrect information
- Implement a workaround without informing stakeholders
- Treat it as a permanent constraint regardless of its origin
Correct answer: Document the finding, validate with stakeholders, and renegotiate the constraint if the assumption is confirmed false
Constraints based on false assumptions should be surfaced to stakeholders for validation and potential revision, as they may unnecessarily limit architectural options.
Question 7: Which metric best measures whether an architectural goal of 'high availability' has been achieved?
- Mean Time Between Failures (MTBF) and Mean Time To Recovery (MTTR) (Correct answer)
- Lines of code per module
- Number of API endpoints exposed
- Cyclomatic complexity of critical components
Correct answer: Mean Time Between Failures (MTBF) and Mean Time To Recovery (MTTR)
MTBF and MTTR are the standard quantitative measures for availability, capturing how often failures occur and how quickly the system recovers.
CPSA Architectural Goals and Constraints 3
A hospital system requires 99.999% uptime for its patient monitoring module.
Which architectural pattern most directly addresses this goal?