A scheme to maximise use of a communications line By giving a larger share of the Bandwidth to the modem at the end which is transmitting the most information. Only one end of the connection has full Bandwidth, the other has only a fraction of the Bandwidth. Normally, which end gets the full Bandwidth is chosen dynamically. Asymmetrical modulation was made famous By the HST mode of the early high-speed modems from US RoBotics. (1998-03-13)