发明名称 Method of discouraging the completion of wrong-number calls
摘要 A method of discouraging the completion of certain classes of calls including wrong-number calls. Incoming calls from calling parties not included on a customer-specified screening list are first connected to an appropriate advisory announcement. Such calls are advantageously not extended to the customer station if the calling party disconnects within a specified time of receiving the announcement. To limit the delay of calling parties, the announcement is bypassed for callers included on the screening list and may be quickly interrupted by the transmission of a single, dual tone multifrequency digit from the calling station.
申请公布号 US4782508(A) 申请公布日期 1988.11.01
申请号 US19860839865 申请日期 1986.03.03
申请人 AMERICAN TELEPHONE AND TELEGRAPH COMPANY, AT&T BELL LABORATORIES 发明人 BORCHERING, JAMES W.;TAFF, LOUIS M.
分类号 H04M3/436;H04M3/487;H04Q3/00;(IPC1-7):H04M3/42 主分类号 H04M3/436
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