DSL
Digital dedicated telephone circuit that permits traditional voice transmissions and high-speed, full duplex digital transmissions to operate on the same line. Three variations of DSL exist: SDSL (symmetric DSL) provides the same transmission rate in directions; ADSL (asymmetric DSL) provides a higher downstream speed (download) than upstream; and VDSL (very high-speed DSL) provides high-speed ADSL tansmissions.
More: Digital Subscriber Line