Abstract: A traffic shaper having a management information collecting unit which collects management information stored in a specific device outside of the traffic shaper and sets a bandwidth control condition based on the management information, and a traffic control unit which controls a bandwidth based on the bandwidth control condition. The traffic shaper is connected between an external network and a relay apparatus connecting a plurality of access endpoints whose bandwidth to the external network are to be controlled by the traffic shaper. The management information collecting unit regularly collects the management information to automatically reflect updated management information in the specific device outside of the traffic shaper.

Abstract: A plurality of bridges are interconnected between respective ports thereof in a ring shape to configure a network containing a redundant route. When a bridge has a blocking port, the bridge transmits to the network a blocking advertisement containing information indicating that it has a blocking port and its address. When a bridge does not have a blocking port, the bridge transmits a line failure notification to other bridges having a blocking port when a line failure is sensed. When a bridge has a blocking port and the line failure notification has been received from other bridges, the bridge transmits to the network a blocking release advertisement indicating that the blocking port has been transited to a forwarding state and the blocking state has been released. When a bridge receives a blocking release advertisement packet, the bridge erases a forwarding database thereof.

Abstract: A plurality of bridges containing an own bridge and other bridges are connected to each other between respective ports thereof in a ring shape to configure a network containing a redundant route. When the own bridge has a blocking port, the bridge transmits a blocking advertisement containing its own address indicating that the port of the bridge has been transited to a blocking state, to the network by a broadcast packet. In the case where the own bridge does not have the blocking port, the bridge transmits a line failure notification to the other bridges having a blocking port when a line failure is sensed. When the own bridge has a blocking port and the line failure notification has been received from the other bridges, the bridge transmits a blocking release advertisement which indicates that the blocking port has been transited to a forwarding state and the blocking state has been released, to the network by a broadcast packet.