Objecteering empowers UML2 – Examples
A requirement specifies a capability or condition that must be satisfied. A requirement can define a function that a system must perform or a performance condition a system must achieve. A requirement can appear in other diagrams to show its relationships to other model elements. Requirements have properties and links to other elements (requirements or model elements).
In the example, requirements are connected to model elements in order to express model elements that refine, satisfy or verify them.
Requirement diagrams are based on the OMG’s SysML (System Modeling Language) standard.