This ReferenceTypecan be used to expose that two different Nodesin the AddressSpacerepresenting the same entity in the real world. Both Nodesmight represent different aspects of the same entity in the same world, or model the same aspect in different ways, for example defined in different companion specifications. For example, an ethernet port of a network module might be represented as an Objectof an ObjectTypedefined by one companion specification focusing on the PROFINET relevant information for such a port and by another Objectproviding a more generic Ethernet and IP focused view on the port defined by an ObjectTypein another companion specification. Both Objectsmay have distinguished information, but also provide some common information like the IP address, potentially in different data formats.

If a Serverexposes more than two Nodesrepresenting the same entity, it is recommended that all of the Nodesreference each other. A Clientshould not rely on all Nodesbeing mutually referenced to each other; i.e., the Clientshould browse each of the Nodeschecking for additional RepresentsSameEntityAs References.

The RepresentsSameEntityAs is a concrete ReferenceTypeand can be used directly. It is a subtype of NonHierarchicalReferences. It is a symmetric Reference, that is, it provides the same semantic in both directions.

The semantic of this ReferenceTypeis to relate two Nodesthat represent the same entity in the real world.

The SourceNodeof Referencesof this ReferenceTypecan be of any NodeClass.

The TargetNodeof Referencesof this ReferenceTypecan be of any NodeClass.

Both, SourceNodeand TargetNodeshall represent the same entity in the real world.

RepresentsSameEntityAs is formally defined in Table 7.

Table 7– RepresentsSameEntityAs Definition















Subtype of NonHierarchicalReferences defined in OPC 10000-5

Conformance Units

Base Info RepresentsSameEntityAs