Screening of address book data, system and manner null for long term observations and automatic operation

摘要

PROBLEM TO BE SOLVED: To attain high precision and high speed and to eliminate call of a customer as an inspection object to almost zero by discriminating the effectiveness of data of a telephone number based on network information which is obtained by means of a disconnection reason obtaining means and outputting a discrimination result. ;SOLUTION: The general telephone line 701 of an analog signal is treated in an analog exchange 602. In the meantime, the both of the general telephone line 702 of the analog signal and the ISDN line 801 of a digital signal are treated in a digital exchange 603. When the line is disconnected in the ISDN line due to the maintenance management of a fault, etc., the reason and the occurrence source of disconnection are obtained by the terminal of a call originating source as a code. Therefore, when the exchange of a final stage connected to the terminal of the customer is a digital system, a disconnection reason code can be obtained even when the line used in the customer terminal is the general telephone line. Thus, the effectiveness of data of the telephone number is discriminated based on network information which is obtained by the disconnection reason obtaining means and its discrimination result is outputted.;COPYRIGHT: (C)1998,JPO