US Patent 7133503 Incoming call control by the called party

A telephony communication device is capable, upon an election by a user, of transmitting a defer answer signal in response to receiving notification of an incoming call. The defer answer signal causes the telephony infrastructure equipment to place the calling party on hold and play a voice message to the calling party requesting that the party remain on hold and preferably informing the calling party that the called party will be able to accept the call within a predetermined time. Upon the called party becoming available to accept the incoming call, the called party retrieves the waiting call by sending a connect call signal from subscriber's communication device.