Introduction

Digital Subscriber Line (DSL) 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 in telecommunications marketing, the term Digital Subscriber Line has been widely adopted as a more marketing-friendly synonym for Asymmetric Digital Subscriber Line (ADSL), the most commonly installed version of consumer-ready DSL. DSL is used simultaneously via the the same telephone line with regular telephone as it uses a higher frequency band that is separated by filtering.

The download speed of consumer DSL services typically ranges from 384 kbit/s to 20 Mbits/s, depending on DSL technology, line conditions and service-level implementation. Typically, upload speed is lower than download speed for ADSL, but the two are equal for the rarer Symmetric Digital Subscriber Line (SDSL) service.

References

1. http://en.wikipedia.org/wiki/Digital_subscriber_line
2. http://www.dslreports.com