III-D.2 The CORBA Topology Service

  The topology service whose goal is to maintain and manipulate the logical topology of distributed systems is currently undergoing the OMG standardization process. It defines mainly three generic APIs that are particularly useful for topology management purposes: The Metadata Manager API allows the definition of rules for topology relationships between object classes based on criteria like their type or the number of objects that take part in a topological relationship. The Data Manager API makes use of the former API for establishing, maintaining or deleting relationships between object instances. Every change requires a lookup for ensuring that the rules defined in the metadata are fulfilled. The Query Manager API, finally, is used by management applications for inquiries concerning topology relationships.

Although these features are particularly useful for managing distributed systems, the standardisation of the topology service has been stopped in december 1997 because it seemed that recent developments in the OMG (Portable Object Adapter, Meta-Object Services) already provide parts of the topology service functionality.