Abstract: A network monitoring system which alleviates workloads imposed on network devices being monitored, reduces network traffic, improves the quality of data transmission, and increases the efficiency of monitoring activities. The system comprises a connection set-up unit which establishes a point-to-multipoint connection between a network device to a plurality of monitoring stations. This point-to-multipoint connection passes through a broadcast unit that serves as a branching point of multiple connections. A status message transmission unit, disposed in the network device, transmits status messages over the point-to-multipoint connection when a status change is detected in the network device. The broadcast unit distributes these messages toward a plurality of monitoring stations in the system. Before reaching the destinations, the status messages are subjected to a status message format conversion unit so as to make their data format suitable for the recipient monitoring stations.

Abstract: An ATM device which can be connected to an ATM network via lines includes a first part setting connections on the lines, and a second part moving a connection on a line to another line if a call setup requests a band greater than idle bands of the lines so that the band requested by the call setup can be set on the line from which the connection is moved.