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Link from Sequence Diagrams

You can associate requirements for system behavior interactions with the model elements that implement the behavior by creating links from sequence diagrams. You can create links from lifelines, gates, messages, fragments, and sequence diagrams themselves. Links from sequence diagrams to requirements contribute to the requirements implementation status in the Requirements Editor.

You can use System Composer™ sequence diagrams to describe expected system behavior as a sequence of interactions between the components of an architecture model. For more information, see Describe System Behavior Using Sequence Diagrams (System Composer).

Create Links

To create links:

  1. Open a sequence diagram in the Architecture Views Gallery (System Composer).

  2. Open the Requirements Editor. In the Views tab, in the Requirement section, click Open Requirements Editor.

  3. In the Requirements Editor, open a requirement set.

  4. Select a requirement.

  5. In the Architecture Views Gallery, select an element in the sequence diagram, or select the sequence diagram itself by clicking the white space in the diagram.

  6. Create the link. In the Views tab, in the Requirement section, click Link to selected requirement.

Sequence diagram with an element selected. The mouse indicates the Link to selected requirements button.

Requirements Toolbox™ sets the link type depending on the type of model element that you link from.

Model ElementLink Type
  • Lifelines

  • Gates

  • Messages

  • Fragments

  • Sequence diagrams


Implementation links contribute to the requirements implementation status. For more information, see Review Requirements Implementation Status.


Verification links from sequence diagrams do not contribute to requirements verification status. For a list of valid requirement verification items, see Review Requirements Verification Status.

View Links

To view the links from the Architecture Views Gallery:

  1. In the Views tab, in the Requirement section, click Requirements Manager. Linked model elements have the Requirements icon .

  2. Select a model element that has the Requirements icon . The Requirement Links pane at the bottom of the screen displays the summary of the linked requirement and the link type.

  3. Click the hyperlink in the Requirement Links pane to view the linked requirement in the Requirements Editor.

Sequence diagram with the Requirement Links pane at the bottom

See Also


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