| 摘要 |
PURPOSE:To unify the control and the processing of various traffic data and traffic opening data, by providing a trunk, which discriminates the audible signal such as a busy-back signal and a ring-back signal, in the exchange. CONSTITUTION:After a selecting signal is transmitted to the next-level station, a service path 31 between a subscriber 2 and a line trunk 24 is set, and an audible signal discriminating trunk 27 is connected to the service path 31 by cutting-in to set a service path 31, and the audible signal is monitored by the audible signal discriminating trunk 27. When the service path 32 is released by a disconnection signal, a central processing device 23 reads the state of the audible signal discrimiating trunk 27, namely, information indicating whether the detected audible signal is busy-back signal or a ring-back signal to measure the traffic opening. |
