4 NodeIds and BrowseNames ToC Previous Next

4.1 NodeIds ToC Previous Next

The NodeIds of all Nodes described in this standard are only symbolic names. OPC 10000-6 defines the actual NodeIds.

The symbolic name of each Node defined in this standard is its BrowseName, or, when it is part of another Node, the BrowseName of the other Node, a “.”, and the BrowseName of itself. In this case “part of” means that the whole has a HasProperty or HasComponent Reference to its part. Since all Nodes not being part of another Node have a unique name in this standard, the symbolic name is unique. For example, the ServerType defined in 6.3.1 has the symbolic name “ServerType”. One of its InstanceDeclarations would be identified as “ServerType.ServerCapabilities”. Since this Object is complex, another InstanceDeclaration of the ServerType is “ServerType.ServerCapabilities.MinSupportedSampleRate”. The Server Object defined in 8.3.2 is based on the ServerType and has the symbolic name “Server”. Therefore, the instance based on the InstanceDeclaration described above has the symbolic name “Server.ServerCapabilities.MinSupportedSampleRate”.

The NamespaceIndex for all NodeIds defined in this standard is 0. The namespace for this NamespaceIndex is specified in OPC 10000-3.

Note that this standard not only defines concrete Nodes, but also requires that some Nodes have to be generated, for example one for each Session running on the Server. The NodeIds of those Nodes are server-specific, including the Namespace. However the NamespaceIndex of those Nodes cannot be the NamespaceIndex 0, because they are not defined by the OPC Foundation but generated by the Server.

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