Models have a UA Namespace. In case they contain definitions complex types, there is also an XML Schema accompanied that uses an XML Namespace for the elements that represent complex content in Value.
Suppose a tool reads in some NodeSet and some values are added and the tool wants to write out the modified NodeSet.
Problem: How does the tool know the XML Namespace belonging to the UA Namespace? Even if the schema file for the model has been given, if there is not already a complex Value contained in the NodeSet, the tool does not know which schema belongs to which Model?!
Possible solutions: Define an algorithm how XML Namespace is built from OPC UA Namespace (add “/Types.xsd” is the behaviour of some tools), or add an Uri XmlNamespace to the Model element here