Acronym for Digital Subscriber Line
Not many people are aware but Telecom is extensively selling SDSL to businesses when they order Ethernet connectivity and fibre to the premises are unavailable, they only need up to 2 Mbps or there will be a delay with getting higher speed product available. It is not sold as SDSL but called other names as Telecom starts to demphasie FrameRelay.
| |ADSL|HDSL|SDSL|VDSL |Bits/second| 1.5 to 9Mbps downstream, 16 to 640 kbps upstream | 1.544 or 2.048 MBps | 1.544 or 2.048 Mbps | 13 to 52 Mbps downstream, 1.5 to 2.3 Mbps upstream |Mode|Asymmetric|Symmetric|Symmetric|Asymmetric |Copper Pairs|1|2|1|1 |Range (24-guage UTP)|3.7 to 5.5 km|3.7km|3.0km|1.4km |Signaling|Analog|Digital|Digital|Analog |Line code|CAP/DMT|2B1Q|2B1Q|DMT |Frequency|1 to 5 MHz|196kHz|196kHz|10MHz |Bits/cycle|Varies|4|4|Varies
-- Taken from "Data and Computer Communications" - William Stalling - 6th Ed, ISBN:0130863882
See also: ADSL2