Assets provide skills / capabilities. It is desirable to describe, what capabilities the asset supports to select the right asset for the right purpose. Depending on the asset, the capabilities can be very different. A temperature sensor has the capability to measure the temperature, whereas an injection moulding machine can produce parts, and the parts depend on the configuration of the machine.
This specification does not define specific types of capabilities. Other specifications, like IEC Common Data Dictionary or ECLASS define common capabilities. Application-specific capabilities, like producing application-specific parts, are related to describing those parts in recipes, jobs or programs. It is expected, that other specifications, dealing with those, may define concepts for those application-specific capabilities.
This specification defines a standardized place where to expose the capabilities. For common capabilities, it is recommended to use dictionary references, as defined in OPC 10000-19, to reference external dictionaries like IEC Common Data Dictionary or ECLASS.
In order to provide access to the capabilities, the concept of a Folder as defined in OPC 10000-5 is used. This specification just defines the use of the standardized BrowseName “Capabilities” (defined in the Namespace of this specification). Servers might provide the capabilities using different access paths, but they should provide the Capabilities Folder as well. This Folder might be organized into other Folders, so Clients shall expect that they need to browse several hops to get to all capabilities. In Figure 8, an example is given, also pointing with dictionary references to an external dictionary (ECLASS).
