HP WBEM Services Software Developer's Kit for HP-UX Provider and Client Developer's Guide A.01

Schema Design and Implementation
Schema Implementation
Chapter 3 49
it could be accomplished if a provider could be certain that all clients
using the class, property, or method were upgraded simultaneously with
the provider. This is very difficult to ensure and is not recommended.
Class "Version" qualifiers
The DMTF uses the major and minor version numbers to reflect which
version of the CIM schema originated a class. The format for class
version numbers is "m.n.u" where:
• m = major version (numeric)
• n = minor version (numeric)
• u = update (errata or DMTF coordinated changes) (numeric)
In CIM Schema version 2.6, for example, the major version number is 2
and the minor version number is 6. For more information, see the section
labeled Schema Versions in the latest CIM Specification.
When upgrading a provider, it is important to be sure that all affected
classes (those which are extensions created by the provider implementer)
have their version number incremented appropriately. When defining
additional subclasses, provider developers can use version numbers
associated with their product as long as they conform to the syntax
described in the list above. It is important to be sure that the major
version number is only incremented when major revisions are made to
the schema (those possibly breaking backward compatibility).
Incrementing the minor version indicates that the schema upgrade will
not adversely impact client applications. The update number can be used
for internal changes relative to a defined (probably released) baseline.
The Version qualifier for the class should only be changed if the class
definition is changed. Developers can use whatever version numbers
they'd like as long as they comply with the rules stated above.
Superclasses Shared with Other Providers
Extensions to the DMTF CIM schema which result in superclasses that
are shared among providers must be handled carefully when considering
a MOF file upgrade. If changes to these shared classes must be
implemented, coordination among those sharing the class is essential.
The "owner" of the shared class must coordinate changes between the
affected parties and adhere to the upgrade policies described above. The