Historical
TR No. 28
High-Bit-Rate Digital Subscriber Line (HDSL)
This Technical Report presents the results of an investigation into the feasibility and advisability of bi-directional high-bit-rate digital subscriber lines (HDSL) that operate over twisted wire pairs in the outside loop plant with a payload capacity substantially greater than ISDN Basic Access DSLs. The Report describes an HDSL system that could provide an alternative to T1 repeatered lines to transport DS1-based services with a nominal rate of 1.544 Mb/s. The Report discusses HDSL system support of the ANSI T1.403-1988 and ANSI T1.408-1990 interface standards. To ensure operation with adequate margin, current technology appears to require a dual-duplex" architecture that uses two transceivers at each end connected by two nonloaded wire pairs that meet Carrier Servicing Areas (CSA) design guidelines."
Alliance For Telecommunications Industry Solutions [atis]