Patent ID: 6625270
Filing Date: 2003-09-23
Classification: H04M

Abstract:
Simplified apparatus at a subscriber location for restricting telephone access to a called subscriber number from the telephone network to only authorized calling parties, said apparatus not including any programmed processor, said apparatus comprisinga caller-id device connected across the line at the called subscriber location, said caller-id device including a caller-id decoder, a caller-id comparator, and an interface circuit; and a connection circuit at the called subscriber location and in the line between the telephone network and the called subscriber, said connection circuit including a switch element for maintaining the line on-hook on reception of a call from the telephone network to the called subscriber, means for limiting the current flow there through across the line to less than the off-hook threshold for the telephone network when a ring signal is applied to the line from the telephone network, and means responsive to said caller-id device for applying a signal to said switch element to allow connection of a call from an authorized calling party to the called subscriber.