The NodeIdsof the Typesdefined in this specification are mandatory and fixed in the provided XML-file. This applies only to the Typesthemselves and not to the child elements. NodeIds of generated instances are not fixed and assigned by the individual OPC UA server. Therefore, the namespace of the NodeIdsis the Local Server URI with namespace index 1 or a vendor specific namespace with vendor specific index. However, a Servershall persist the NodeIdsof the generated Nodes, that is, it shall not generate new NodeIds when rebooting.

NOTE: It is not mandatory that the servers of all machines from one manufacturer use the same NodeIds for the individual instances, so a client cannot expect this. Also, a software update of a machine may lead to new NodeIds.