Abstract: A system for controlling topology views for operators in network management includes a data-storage unit which stores data of a base topology view, a security-management unit which controls access-authorization information with respect to each of the operators, the access-authorization information for a given operator defining network elements accessible by the given operator, and a topology-view-management unit which generates data of a dependent topology view by making a partial copy of the data of the base topology view only with respect to the network elements accessible by the given operator, thereby providing the dependent topology view to be presented to the given operator.

Abstract: The present invention relates to a method of rerouting a PVC route on an ATM network by previously defining an alternate route for the PVC route and by switching the PVC route to a previously defined alternate route when a fault occurs in a network element forming the PVC route.

Abstract: A network management device for managing a plurality of network elements has a network element management data acquisition unit for acquiring, in stages, various management data possessed by the network elements when a session with a network element is resumed and when the network management device itself is started up, a rule management table for storing a dependence relationship between an operation and management data necessary to execute the operation, a feasible operation decision processing unit which, when an operation has been specified, refers to the dependence relationship to determine whether management data necessary to execute the operation has been acquired. If the necessary management data has been acquired, a network management execution unit executes network management conforming to the operation.