Caller discrimination within a telephone system

摘要

A method is provided for a telephone subscriber to distinguish between callers. The method is accomplished by storing a pass code for a subscriber's telephone within a memory of the telephone system. Callers who have been informed of the pass code and who call the subscriber's telephone and enter the pass code receive special treatment. For example, upon the caller calling the subscriber's telephone, a normal ringing pattern is applied to the subscriber's telephone while a ring back signal is returned to the caller. Upon the caller entering the pass code, a special ringing pattern is applied to the subscriber's telephone. The special ringing pattern is different than the normal ringing pattern and thus indicates to a subscriber of the subscriber's telephone, even before the telephone is answered, that the caller is one of a select group of callers to whom the subscriber has shared the pass code.