What is URN

The User Requirements Notation (URN) is a standardized semi-formal, lightweight graphical language for modeling and analyzing requirements in the form of goals and scenarios and the links between them. It comprises two complementary languages: the Goal-Oriented Requirement Language (GRL) and the Use Case Maps (UCMs).

URN supports for the elicitation, analysis, specification, and validation of requirements. It allows systems, software, and requirements engineers to specify requirements for a new system or an evolving system, and analyse such requirements for correctness and completeness. URN models can be used to specify and analyze various types of reactive systems, business processes, and telecommunications standards.

URN explicitly addresses goals (non-functional requirements with GRL) in addition to scenarios (functional requirements with UCMs) in a graphical way in one unified language. It is standardized by International Telecommunication Union as recommendation:

ITU-T Z.150 series

• ITU-T Z.150 (02/03)
  User Requirements Notation (URN) - Language requirements and framework
• ITU-T Z.151 (11/08)
  User requirements notation (URN) - Language definition

More information on:

• ITU-T Z.150 recommendation.
• https://jmbruel.github.io/teachingMaterials/urn.html.