If the text part of a value of DataType LocalizedText, like the Manufacturer or the Model of a Machine, is language neutral, i.e. it is the same in all languages, the locale of the LocalizedText shall be null or an empty string.
If the information for optional nodes (e.g. Properties) is not available and the access is read-only, the optional Node shall not be provided.
If the content of optional nodes is writable, i.e. it can be provided by end-users, system integrators, etc., it is desirable to provide the Nodes to allow the usage of them.