Page 146 - Software and Systems Requirements Engineering in Practice

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Ideally, the requirements prototype will be reusable for
construction of the actual product. This will only happen if the target
language, coding standards, and architecture are known prior to the
start of model construction. Unfortunately, those facts being known,
the model might wind up being “skewed” toward development.
4.7 Determining Model Completeness
Models are reviewed for completeness by looking at three areas:
diagram quality, content correctness (reviewed with subject matter
experts), and model faults. The criteria for completeness should have
been defined prior to the start of modeling.
Diagram Quality
Diagrams should be reviewed for clarity and completeness. Upon
acceptance of a diagram, its status can be changed from draft to
accepted. In order for a model to be accepted, every diagram in the
model should have a status of accepted. Depending on the
organization’s specific quality assurance procedures, an MDRE model
could pass conditionally if diagrams have minor changes to be made
and those changes
• Are well understood.
• Are quickly accomplished.
• Do not change the semantics of the model.
• Do not impact other parts of the model.
Content Correctness
Content correctness is accomplished by having subject matter experts
and analysts review reports and documents generated from the
model. The following criteria are applied:
• Every use case, whether abstract or concrete, must have a text
definition that is meaningful and correct.
• Every concrete use case with extending or included use cases
must have at least one activity or sequence diagram describing
its logic.
• Every boundary (user interface or software interface) must be
shown on at least one diagram explaining how it is used, and
that explanation must be correct.

Model Faults That Should Be Corrected
Before a Model Is Completed
Some MDRE model faults are serious and, if not corrected, can lead
to problems during development. Where possible, the fault checks