Topic summary
HDSL
Extracted from the Wikipedia article High-bit-rate digital subscriber line.
Comparison to other DSL variants
HDSL gave way to new symmetric DSL technologies, HDSL2 and HDSL4, the proprietary SDSL, and G.SHDSL. HDSL2 offers the same data rate over a single pair of copper; it also offers longer reach, and can work over copper of lower gauge or quality. SDSL is a multi-rate technology, offering speeds ranging from 192 kbit/s to 2.3 Mbit/s, using a single pair of copper.