You use the StV-4 Capability Dependencies diagram to show the capabilities (or capability functions) that are of interest to the architecture. You can group capabilities into logical groupings, or “clusters”. These clusters serve to inform the acquisition process and are presented in the Capability Phasing (StV-3) report.

The elements in an StV-4 View are not intended to represent individual systems or items of equipment. Military capability can be satisfied by a group of systems, and an individual system can satisfy more than one capability. You can specify this many-to-many mapping in the Capability to Functional Resource matrix (StV-5).

Below is an example of an StV-4 Capability Dependencies diagram. All rectangular symbols on the diagram, both big and small, represent Capabilities. The lines drawn between Capabilities are Capability Dependency lines. Some Capabilities are shown drawn in other Capabilities; this denotes composition of Capabilities.

You can use the following basic symbols in the StV-4 Capability Dependencies diagram:

A high level user requirement, usually functional. Capabilities may be nested. A Capability that encloses other Capabilities may be regarded as a cluster or group. A capability may have performance metrics represented as Physical Properties. Note that some capabilities might be called “Capability Functions” - MODAF does not distinguish between Capability Functions and Capabilities, other than by virtue of their position in a hierarchy.

There is a parent-child relationship between two capabilities: the relationship indicates one capability (child) is a sub-capability of the other (parent). Although the MOD tends to work in terms of capabilities and capability functions, it is not always apparent that there is any difference between them other than their relative positions in an StV-2 Capability Taxonomy diagram.

A relationship which asserts that a capability (‘to’ Capability) is dependent on another (‘from’ Capability) capability.