A self-contained modem that is connected to the serial or USB port of a computer. The older serial port models draw power from a wall outlet and have the advantage of status lights on the outside of the case that show the changing states of the modem (off-hook, carrier detect, transmitting, etc.). The term may also refer to broadband modems for cable and DSL use. Contrast with
internal modem. See
USB modem,
cable modem and
DSL modem.
External Modem
The status lights on this external Courier V.Everything modem keep the user informed throughout the communications session and help to pinpoint the problem when something goes wrong. (Image courtesy of U.S. Robotics.)