HDSL — High-bit-rate DSL; uses two pairs of copper wires; E1/T1 data rates; distances up to 3657 metres over 24 AWG copper.

SDSL — Symmetric DSL; uses a single pair of copper wires; multiple data rates of up to 2.3 Mbps; distances up to 3657 metres over 24 AWG copper.

G.SHDSL — G.991.2 (ITU) Symmetric High-bit-rate DSL; uses a single pair of copper wires; data rates up to 2.3 Mbps; distances up to 4267 metres over 24 AWG copper.

M/SDSL — Multirate SDSL; uses one pair of copper wires; changing data rates of 2 Mbps; distances over 24 AWG copper up to 8839 metres at 64 or 128 kbps or 4572 metres at full 2 Mbps.

HDSL2 — High-bit-rate DSL2; uses one copper wire pair; E1/T1 data rates.

RADSL — Rate Adaptive DSL; symmetric or asymmetric; uses one pair of copper wires; data rates from 1–7 Mbps downstream (to the user) and 128 kbps–1 Mbps; distances up to 5486 metres over 24 AWG copper.

G.Lite — G.991.2 (ITU) standard based on ADSL; uses one pair of copper wires; data rates of 1.5 Mbps downstream, 512 kbps upstream; supports fast retrain; no need for splitter.

IDSL — ISDN DSL; uses one pair of copper wires; data rates up to 144 kbps; distances up to 7924 metres over 24 AWG copper.

ADSL — Asymmetric DSL; uses one pair of copper wires; data rates of 1.5– 8 Mbps downstream and 64–640 kbps upstream; distances over 24 AWG copper up to 5486 metres at 1.5 Mbps and 1828 metres at 7 Mbps.

VDSL — Very high-speed DSL; uses a single copper wire loop; data rates up to 52 Mbps downstream and 26 Mbps upstream; limited distance (around 3280 metres).

ReachDSL™ — Symmetric/asymmetric; uses one pair of copper wires; data rates up to 1 Mbps; distances up to approximately 9144 metres over 24 AWG copper. (Nonstandard.)