LINE CONNECTION CONTROLLING METHOD

摘要

PURPOSE:To attain sure line connection by transmitting a connection end signal to both terminal devices at the same time after an exchange of a calling station confirms the end of connection of a calling station and a called station. CONSTITUTION:A terminal device 2 makes a call and a calling reception message is given from an exchange 21 of a called party to an exchange 21 of a calling party. The exchange 21 connects a terminal device 22 of the called party and a relay line 20 with a channel switch 32 after transmitting the calling reception message. The exchange 1 supervises the relay line 20 and awaits that the exchange 21 connects the device 22 and a relay line 20 by the channel switch 32. When the exchange 1 detects that the switch 32 is set, the exchange 1 connects a signal transceiver 13 to the relay line 20 by using a switch 12. Then the connection end signal is transmitted from the transdceiver to the devices 2, 22.