It runs over one pair of copper wires, with a maximum range of 10,000 feet (3,000 m).
It cannot co-exist with a conventional voice service on the same pair as it takes over the entire bandwidth.
[2] SDSL is often confused with G.SHDSL and HDSL;[3] in Europe, G.SHDSL was standardized by ETSI using the name 'SDSL'.
As there is a standardised successor available, SDSL installations today are considered legacy.
[citation needed] SDSL typically falls between ADSL and T1/E1 in price and was mainly targeted at small and medium businesses which don't need the service guarantees of Frame Relay or the higher performance of a leased line.