What is URN?

ITU-T Study Group 10 (now Study Group 17) has started, in November 2000, work towards the standardization of a User Requirements Notation (URN) that targets the representation of requirements for future telecommunication systems and services. At this early stage of its development, URN contains one notation for the representation of non-functional requirements (NFRs) and a complementary scenario notation for functional requirements. NFRs are seldom captured explicitly in design processes (even in UML), and URN is a first standardization effort in that direction. The NFR notation being proposed is the Goal-oriented Requirement Language (GRL). The scenario notation is based on Use Case Maps (UCM) and hence abstracts from message exchanges. URN fits nicely in the very first stage of existing design and standardization methodologies. On top of traceability links between GRL and UCMs, the proposed standard intends to provide additional insights on the derivation of other models, including Message Sequence Charts, performance models (e.g. LQN), and test cases. Links to the UML standard will also be investigated in order to unify common concepts and perhaps notations. The URN Focus Group leads the development of URN standard.