namespace
A container for node IDs (points in the framework). The
OPC foundation specifies a predefined namespace with index 0. Many
more namespaces belong to specific OPC UA specifications, for example,
DI and PLCopen. Every OPC UA specification defines its own node IDs.
(from https://stackoverflow.com).
The OpcUaNamespace component under the OpcUaNetwork node in the Nav tree configures the namespace. The OpcUaServerPointDeviceExt component uniquely identifies each specific node.