DSL(INTERNET)

DSL or xDSL is a family of technologies that provides digital data transmission over the wires of a local telephone network. DSL originally stood for digital subscriber loop, but as of 2009 the term digital subscriber line has been widely adopted as a more marketing-friendly term for Asymmetric Digital Subscriber Line (ADSL), the most popular version of consumer-ready DSL. DSL can be used at the same time and on the same telephone line with regular telephone, as it uses high frequency bands, while regular telephone uses low frequency.

The download speed of consumer DSL services typically ranges from 384 kilobits per second (kbps) to 20 megabits per second (Mbps), depending on DSL technology, line conditions and service-level implementation. Typically, upload speed is lower than download speed for ADSL and equal to download speed for the rarer Symmetric Digital Subscriber Line (SDSL).
DSL (VDSL) typically works by dividing the frequencies used in a single phone-line into two primary "bands". The ISP data uses the high-frequency band (25 kHz and above) whereas the voice utilizes the lower-frequency band (4 kHz and below). (See the ADSL article for information on the subdivision of the high-frequency band.) The user typically installs a DSL filter on each phone outlet. This filters out the high frequencies from the phone line so that the phone sends or receives only the lower frequencies, and the user hears only the human voice. The DSL modem and the normal telephone equipment can be used simultaneously on the line without interference from each other provided that filters are used for all voice devices.