Requirement diagram
A requirement diagram is a diagram specially used in SysML in which requirements and the relations between them and their relationship to other model elements are shown as discussed in the following paragraphs.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Requirements_Diagram.png/237px-Requirements_Diagram.png)
Derive requirement relationship
[edit]If a requirement is derived from another requirement, their relation is named "derive requirement relationship".
Namespace containment
[edit]If a requirement is contained in another requirement, their relation is named "namespace containment".
Satisfy relationship
[edit]If a requirement is satisfied by a design element, their relation is named "satisfy relationship".
Copy relationship
[edit]If a requirement is a copy of another requirement, their relation is named "copy relationship".
Verify relationship
[edit]If there exists a relation between a requirement and a test case verifying this requirement, their relation is named "verify relationship".
Test case
[edit]A test case is defined by a flow checking whether the system under consideration satisfies a requirement.
Refine relationship
[edit]If a requirement is refined by other requirements / model elements, the relation is named "refine relationship".
Trace relationship
[edit]If there exists a relation between a requirement and an arbitrary model element traced by this requirement, their relation is named "trace relationship".
References
[edit]- Weilkiens, Tim (2008). Systems Engineering with SysML/UML: Modeling, Analysis, Design. Morgan Kaufmann / The OMG Press. ISBN 0-12-374274-9.