False call protecting apparatus for use with telephone exchange system and false call protecting method

摘要

When a false signal received from a telephone set on a false originating side is detected, a call thereof is immediately disconnected. In reality, the system comprises a detecting portion 5A and a signal unit 4. The detecting portion 5A detects a false signal according to international telecommunication standard ITU-T No. 5 signal system. The signal unit 4 disconnects the call when the detecting portion 5A detects a false signal. The system further comprises a supervising means that supervises a false signal using toll-free service with a credit card system. A supervising unit 5 supervises whether or not a false signal is present. Corresponding to the supervised result of the supervising means, when a false signal is detected, the signal unit 4 immediately disconnects the call. Thus, the performance of the telephone exchange system is improved. In addition, the security of the system is improved.