Page 53 - Software and Systems Requirements Engineering in Practice

26 S o f t w a r e & S y s t e m s R e q u i r e m e n t s E n g i n e e r i n g : I n P r a c t i c e

Testable Requirement

Nonfunctional Testable Functional Testable
Requirement Requirement

Performance Reliability
Requirement Security Requirement Requirement

Transactions per Second
Average
SOC Extensions
Peak Transactions per
Second

FIGURE 2.5 Sample extension of a taxonomy

Taxonomy Extension
To extend a taxonomy is a rather simple undertaking. The classification
tree is extended with artifacts of the appropriate classification (see
Figure 2.5). Figure 2.6 illustrates how detailed a taxonomy can become.

Business Needs Artifacts
Business & Customer System Vision Conditions &
Requirements Scope
Business Customer Assumptions General Scope &
Objectives Requirements Main Features Dependencies Conditions Limitations
Customer/Market Scope of
Background Functional
Requirements Initial Release
Value to the Quality Scope of
Opportunities
Customer Nonfunctional Subsequent
Releases
Objectives Limitations &
ROI & Risk System Success Exclusions
Factors
ROI Business Risk Key Features/
Calculation Analysis Risk Calculation Requirements
Cost/Benefit Feasibility Market/ Priority of
Analysis Study Customer Requirements
Long-term ROI Impact
Analysis Analysis Technology
Volatile/Vague
Requirements
Supply Guarantee
Reliability
Organizational
Time/Effort/
Cost
FIGURE 2.6 Taxonomy of business needs artifacts