The NATO System Functionality Descriptions (NSV-4) address human and system functionality. The primary purposes of NSV-4 are to develop a clear description of the necessary data flows that are input (consumed) by and output (produced) by each resource, ensure that the functional connectivity is complete, and ensure that the functional decomposition reaches an appropriate level of detail. The System Functionality Description provides detailed information regarding the allocation of functions to resources and flow of data between functions. The NSV-4 is the systems view counterpart.
NSV-4 can be represented using:
A NSV-4 diagram for Function hierarchies. This diagram is based on the UML Class diagram.
An NSV-4 diagram for Function flows. This diagram is based on the UML Activity diagram.
A UML Class diagram.
A UML Activity diagram.
A SysML Block diagram.
A SysML Activity diagram.
Fragment of NSV-4 System Functionality Description Flow
You can also create NSV-4 Business Process Diagram (BPD). In order to do that, use the Cameo Business Modeler plugin. For more information on how to model the business process diagram, see BPMN Process Diagram.
An NSV-4 is the behavioral counterpart to the NSV-1 (in the same way that NOV-5 is the structural counterpart to NOV-2).
The functions are likely to be related to Operational Activities captured in an NOV-5. Although there is a correlation between the Operational Activity Model (NOV-5) and the functional hierarchy of NSV-4, it need not be a one-toone mapping, hence, the need for a Function to Operational Activity Traceability Matrix (NSV-5), which provides that mapping.