UML Modeling Techniques > Object interaction modeling > Sequence diagram > Timing constraints > Creating timing constraints on a sequence diagram
  
Creating timing constraints on a sequence diagram
1. On the Sequence Diagram toolbar, click the Timing Constraint button.
2. Click on the first Statement to which the timing constraint applies.
3. Click on the second Statement to which the timing constraint applies.
4. Drag the Timing Constraint to the required position on your diagram.
5. Open the Timing Constraint's Property Pages.
6. If you want to link the Timing Constraint to a Constraint:
a. Click the Items tab.
b. Click the Link button.
c. Select the check box associated with the appropriate Constraint, and then click OK.
d. Set the Name and
Worst Measurement properties of the linked Constraint as required.
7. If you do not want to link the Timing Constraint to a Constraint:
a. Click the Timing Constraint tab.
b. In the Caption box, type a caption for the Timing Constraint.
c. In the Time box, type the timing constraint including any units.
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The diagram view options determine whether Timing Constraints are shown or hidden.
When a Timing Constraint is not linked to a Constraint, the Caption and Time properties of the Timing Constraint are displayed on the Sequence Diagram.
When a Timing Constraint is linked to a Constraint:
The Name and Worst Measurement properties of the linked Constraint are displayed when you select the Timing Constraint on the Sequence Diagram.
You can detach the linked Constraint by right-clicking the Timing Constraint, and then clicking Detach Dictionary Item.