Difference Between DSL and ADSL

Many of us may already know that there is no any difference between DSL and ADSL; the latter is a type of the former. To understand better, one should foremost construe the terms, DSL and ADSL, individually. Let us first see what DSL is all about, before we start to discuss on ADSL.

?What is DSL

DSL (Digital Subscriber Line), also referred as xDSL (x stands for different DSL techniques), is a group of technologies that provide high-speed Internet access, by using the ordinary telephone lines.

It converts the ordinary telephone line into a high-speed passage for digital audio, video and data. DSL technology is widely used for business and personal purpose. The technology is simple as the setup required for network already exists. It does not keep the telephone line busy as is the case in the Imternet access used in the Dial-up connection. However, the speed depends on the distance between the Internet service provider and the user. More the distance, less will be the speed of the Internet access.

?What is ADSL

ADSL is a type of asymmetric DSL which allots more bandwidth for downstream than upstream. The downstream speed (1.5-9 Mbps) is higher than the upstream speed (1.5 Mbps). The downstream speed depends on the distance of the user from the service provider.

The speed increases with decrease in the distance. 1.5 Mbps downstream speed can be achieved for 18,000 feet distance; while 9 Mbps speed is possible for distance of 9,000 feet. Most of the Internet users aim at high downloading, as compared to uploading on network. ADSL is widely used for Internet connections used at home and small businesses. With the help of ADSL, large unused bandwidth of the copper wired network can be utilized for high speed data transfer. With help of ADSL, one can talk on the telephone and simultaneously access the Internet. Following are other types of Asymmetric DSL:
RADSL: The speed of data transfer is adjusted automatically depending on the quality of telephone line and distance from the service provider. The downstream speed is adjusted higher than the upstream speed. RADSL provides a faster speed for premises close to the service provider.
VDSL: It provides a high speed of data transfer for short distance, by connecting to ONU (Optical Network Unit), which is a combination of fiber optic and copper wire networks.