In a communication network, the network management system NMS keeps one or
more element management system EMS in synchronization of network topology
changes using requests that are automatically generated or manually
requested and then sent from the NMS to the affected EMS(s) whenever a
node topology change is made at the NMS. Examples of changes are node
creation, node move, node group move, node group renaming, etc. As the
changes are completed in the EMS topology database, the EMS sends
acknowledgments of the request to the NMS. This functionality requires
verification of the validity of the request for that specific EMS, before
the change is implemented at the NMS.