| 摘要 |
PURPOSE:To reduce the scale of installation and the cost by monitoring an idle state of a subscriber line and a setting a connection path to an opposite equipment connecting to a relay line via an exchange network when a fault takes place in the relay line. CONSTITUTION:Number of subscriber lines accommodated by a packet exchange 1 is set smaller than the number of connected opposite devices 100 and an idle/busy management means 400 monitors the idle/busy state of a subscriber line 400. A connection change means 500 changes the connection to a relay line 2 whose fault is detected by a fault detection means 300 to the subscriber line 4 discriminated to be idle by the idle/busy management means 400. When the fault detection means 300 detects a fault in the relay line 2, a spare connection control means 600 gives a call to the subscriber 4, to set the connection path to the opposite equipment 100 connected by the relay line 2 via an exchange network 200. Thus, number of required subscriber lines is saved and the installation scale and the cost of a packet exchange are saved. |
