Method and apparatus for processing coded information received through a telephone line during the inter-ringing periods

摘要

A method for processing coded information received through a telephone line during the inter-ringing periods. A calling party dials a desired phone number and, once he recognizes the signals indicating that the ringing circuit has been established, he dials a pre-established code during one or more of the inter-ringing periods. Once the code has been received, it is decoded and compared with pre-established codes stored in a memory device. If coincidence is determined, the call is validated via the indicating means. The called party receives an indication that the call is originated by a person who is in possession of the code, and he may elect to answer or not answer the call. If the called party answers the call, the loop is closed and a conversation may take place. Further features include provision for a second code to be sent by the calling party once the loop has been closed, and means for liberating the line, after a certain ringing time has elapsed, when the called party does not answer.