ADSL – What is it, definition and concept

ADSL technology consists of a digital information transmission and access network via the Internet. It is mainly characterized by having the telephone network as infrastructure support.

In other words, the ADSL network allows the sending and downloading of information, giving the user access to the Internet. On the other hand, the meaning of the acronym comes from English: Asymmetric Digital Subscriber Linewhich translated into Spanish would be: ‘Asymmetric Digital Subscriber Line’.

History of ADSL

The origin of this technology dates back to the decade between 1950 and 1960, since what was intended was to improve the performance of the telephone line. This became apparent in the 1980s, when the American company Bellcore managed to patent the technology as a result of its predecessor ISDN (Integrated Services Digital Network), which was the forerunner of ADSL along with other technologies of the time.

On the other hand, it was not until the end of the 90’s when the consumer experienced the benefits that ADSL had over the telephone line at home. This made it become an absolute protagonist in the Internet access network in the first decade of the 21st century.

However, ADSL technology is relegated to playing in the background despite the improvements that occurred with ADSL2+, which increased the speed of uploading and downloading data. ADSL is facing a new competitor that had been developing alongside it: fiber optics.

The evolutionary process of fiber optics follows a path similar to that of ADSL. It is also true that by not using the telephone network, its potential in terms of development is greater. Proof of this is that there are countries like Spain where fiber optics is rapidly displacing private ADSL lines in large cities.

See also  What to do to change jobs?

ADSL is currently only an option if fiber cannot be contracted, since transmission speeds can be 30 times faster in the latter.

How does ADSL and fiber work?

ADSL is a technology that uses the telephone line for its data transmission. Therefore, you must share the network with voice calls.


This means that the development and evolution of technology is limited by the infrastructure itself. Although, it is also true that the range capacity due to the use of this network is almost total.

On the other hand, fiber optics has a direct connection system, which must be installed, but it is direct:


The foregoing gives rise to its own network with which the limits of evolution are established by the technology itself. Possible interference between two uses (telephony and Internet) on the same network and all the problems it presents are also eliminated.

Comparison: ADSL vs Fiber

Although it is true that to access the Internet it does not have to be only via ADSL or fiber, these are the main technologies in the professional and private desktop environment.

Other options to choose from could be the almost extinct modems or the 4G and 5G technologies in mobile devices.

Characteristics ADSL Optical fiber
Infrastructure ☑️
Speed ☑️
Stability ☑️
Bandwidth ☑️

As can be seen, fiber offers greater speed, stability and bandwidth. Despite this, there is a factor that makes it possible for ADSL to remain alive in many countries, and that it is even the majority in number of connections, and that is the infrastructure.

As mentioned above, ADSL technology is based on the telephone network, and this is a basic network that exists in practically all countries in a generalized way. On the other hand, by requiring a separate infrastructure, the installation of fiber optics in areas with a complex geography or with a low population rate drives up costs, so ADSL is the best option in this type of situation that is not in absolutely isolated.

Leave a Comment