Glossary · Semantic interoperability and information models
OPC UA NodeSet
Also known as: NodeSet file, NodeSet2 file, UANodeSet
German: OPC-UA-NodeSet
In OPC UA, a NodeSet is an XML file that describes an information model, such as object types, variable types, data types, references and instances, in the standardized UANodeSet schema defined in OPC 10000-6, so that it can be exchanged between tools and loaded into OPC UA servers and clients.
- Information models
- Standards
In one sentence
An OPC UA NodeSet is an XML file in a standard schema that describes an information model so tools and servers can load it.
Example
The engineer imports the NodeSet of a companion specification into the server configuration tool and then creates machine instances based on its types.
How it applies
- Engineering: NodeSets are the machine-readable form of information models. Modeling tools generate them, and SDKs and servers load them to create the address space.
- Integration: NodeSets depend on each other, for example on the base model and other companion specifications. Load them in the right order and use matching versions.
- Documentation: Deliver the NodeSet of a product's own information model together with human-readable documentation of the nodes. Keep both in sync and version them together (Data model version).
NodeSet vs. address space
A NodeSet is a file that describes nodes. The address space is the set of nodes a running OPC UA server actually exposes, which may combine several NodeSets and dynamically created instances.