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4.10 Design Model Structure
The design model structure is flexible and dependent upon
• Granularity of model for parallel development.
• How close the design model (solution) matches the analysis
model.
Tracing Requirements Through the Design Model
Tracing of requirements through the design model (see Figure 4.26)
can be accomplished as follows:
• Ensure that all requirements in the requirements database (if
used) trace to one or more use cases in the analysis model.
For “child” requirements, it is acceptable for the parent
requirement to trace to a use case.
• Every concrete use case or requirement as shown in the
analysis model must be realized by one or more use case
realizations in the design model.
• All software classes or components in the design model are
associated with one or more use case realizations. Association
means that they are shown on class diagrams that are owned
by the respective use case realization or one of its
derivatives.
• Wherever possible, have the package structure in the design
model mirror that in the analysis model.

Intermodel Quality Assurance Checks
Some quality assurance checks can be performed to ensure that the
analysis and design models are synchronized.

1. Can every requirement be traced to a component, either
directly or indirectly?
2. Can every component be traced to a use case?
3. Can every concrete use case trace to a component?
4. Are there test cases for each component?

Requirements Database
Analysis Model Design Model
• Team Requirements
• Coach
• Players
Team Management Team Management

FIGURE 4.26 Tracing from design to requirements