an upstream transceiver , coupled to an upstream end of a long haul , single digital subscriber loop of an extended range asymmetrical digital subscriber line communication system , ‘ spoofs ’ a digital subscriber line access multiplexer to reduce its downstream data rate over a short haul loop to the upstream transceiver . the reduced downstream data rate is compatible with the data rate that can be supported by the long haul loop and also accommodates an auxiliary pots channel thereover . the reduced data rate may be derived by preliminary signal quality measurements upon the long communication loop conducted between the upstream transceiver and a downstream transceiver coupled to a remote end of the long haul loop .