A.7 Defining ReferenceTypes

Defining new ReferenceTypes should only be done if the predefined ReferenceTypes are not suitable. Whenever a new ReferenceType is defined, the most appropriate ReferenceType should be used as its supertype.

It is expected that Servers will have new defined hierarchical ReferenceTypes to expose different hierarchies, and new Nonhierarchical ReferenceTypes to expose relationships between Nodes in the AddressSpace.