The ConnectsTo ReferenceType is a concrete ReferenceType used to indicate that source and target Node have a topological connection. It is both hierarchical and symmetric, because this is natural for this Reference. The ConnectsTo Reference exists between a Network and the connected Devices (or their ConnectionPoint, respectively). Browsing a Network returns the connected Devices; browsing from a Device, one can follow the ConnectsTo Reference from the Device’s ConnectionPoint to the Network.
The ConnectsToParent ReferenceType is a concrete ReferenceType used to define the parent (i.e. the communication Device) of a Network. It is a subtype of The ConnectsTo ReferenceType.
The two ReferenceTypes are illustrated in Figure 23.
Figure 23 – Type Hierarchy for ConnectsTo and ConnectsToParent References
Table 39 – ConnectsTo ReferenceType
|Subtype of HierarchicalReferences ReferenceType defined in OPC 10000-5.|
Table 40 – ConnectsToParent ReferenceType
|Subtype of ConnectsTo ReferenceType|
Figure 24 illustrates how this Reference can be used to express topological relationships and parental relationships. In this example two Devices are connected; the module DPcomm is the communication Device for the Network.
Figure 24 – Example with ConnectsTo and ConnectsToParent References