You use the SOV-1 diagram to model the taxonomy of your services: what each service name is and what it does, and the structure of services.
You use the Service Taxonomy View (SOV-1) to specify a hierarchy of services. The elements in the hierarchy are service specifications (rather than service implementations), and the relationships between the elements are specialisations. The term specialisations means that one service is a special type of another.
The purpose of an SOV-1 is to provide a governance structure for a Service-Oriented Architecture. Along with SOV-2, it specifies a standard library of service specifications for an enterprise, with which service implementers are expected to conform.
According to the MODAF 1.2 specification, an SOV-1 is structured using only one type of specialisation relationship between elements: sub-supertype, otherwise called inheritance or generalization. This is a relationship between two classes with the child being a pure specialization of the parent, providing all of the same input and output interfaces, attributes and methods, and also having the ability to add functionality and interfaces.
To create an SOV-1 diagram
1 Create a new class diagram. Right-click the Diagrams group in the Explorer (browser); then click New.
2 Name the diagram.
3 In the dialog box that opens, specify the Package that the diagram belongs to, and the Programming Language.
4 Specify that the diagram is of stereotype SOV-1 Service Taxonomy by doing this:
•Open the Properties dialog box for the diagram. Right-click an empty area of the diagram workspace; then click Diagram Properties.
•Navigate to Page 2 of the Diagram Properties dialog box. In the Stereotype list, select SOV-1 Service Taxonomy.
•Save the diagram and refresh the Explorer browser.
The new diagram, with the diagram stereotype, is displayed in the Explorer browser.
This is an example Service Taxonomy diagram from the MODAF literature, as modeled in System Architect.
In the example above, an attribute named availability is specified for the top-level service in the taxonomy. All services inheriting from that service inherit the attribute. The service “Warfighting Service” sets a constraint (also known as “Service Policy”) that the availability shall be greater than 95%. This policy is inherited by the situational awareness services, “Situation Picture” and “Situation Info Consolidation”. and “Situation Info Storage”. Note that policy can be overridden in specialized services, in this case, “High Uptime Situation Info Storage”.
