Abstract: A switch device adapted to interface an incoming telephone line and an internal telephone system comprising a telephone, a facsimile machine, and an auxiliary device such as a modem, answering machine, or another telephone. The switch device automatically receives and answers incoming communications and asks for an identifying code from the caller which will characterize the incoming communication. After characterizing the incoming call, the switch device then alerts the telephone user or the facsimlile machine or the auxiliary device that there is an incoming communication. The non-alerted units are blocked out. A programming mode is provided to prioritize or selectively channel calls that are unidentifiable by the switch device to a preselected default device so that no incoming calls will be lost.