ADSL is an asymmetric Internet access technology. It is an asymmetric system in its structure and allows you to work with connections at speeds up to 8 Mbps. ADSL-technology, the transmission speed of which is calculated up to 1 Mbps, operates on average at a distance of more than 5 km. Today we will look at what this type of connection is and how it works.
History of Appearance

Before answering the question: "ADSL - what is it?", we bring to your attention some historical data. For the first time, high-speed connections were discussed in the late 80s, when even the Internet in its modern form was only an obsession. Its main task in 1989 was to improve and modernize the technology of data transmission over copper telephone wires. Analog-to-digital conversion was created mainly for the rapid transfer of information between various interactive services, video games, video files, as well as for obtaining instant remoteaccess to LAN and other network systems.
Modern ADSL technology: how it works
The action of the network is based on the subscriber's digital line, which provides access to the Internet through telephone communication channels. But telephone lines use an analog signal to carry voice messages. An ADSL connection is designed to convert an analog signal into a digital one and transfer it directly to a computer. At the same time, unlike already outdated Dial-up modems, ADSL-based devices do not block the telephone line and allow you to use digital and analog signals simultaneously.
The essence of the technology (asymmetry) lies in the fact that the subscriber receives a huge amount of data - incoming traffic, and transmits a minimum of information from himself - downstream traffic. As an input, various kinds of content are meant: video and media files, applications, programs, graphic objects. Downstream sends only important technical information - various commands and requests, emails and other minor elements. The asymmetry is that the speed from the network to the subscriber is many times higher than the speed from the user.

The most important advantage that ADSL technology has is its budget and economy. The fact is that the same copper telephone wires are used to operate the system. The number of twisted pairs in them, of course, significantly exceeds the number of similar elements in cable modems. But at the same time, no modernization of switching equipment and complex reconstruction can be carried outneed. ADSL connects quickly, and modern types of modems are intuitive to manage and configure.
What equipment is used for this connection?
In order for the technology to work, special types of modems are used, which differ in their structure, design, connection type:
- PCI modems (computer internals).
- External modems with USB connection type.
- Ethernet interface devices.
- Router, routers with Ethernet scheme.
- Profile types of modems (for security companies, private telephone lines).
- Router with internal Wi-Fi hotspots.
Optional equipment: splitters and microfilters
We must not forget that to connect such a gadget as an ADSL modem, you will need splitters and microfilters. Devices are selected in accordance with the design of the telephone cable. In a situation where a cable outlet is made (or can be done) to separate the modem and telephone channel, a splitter is used. Otherwise, you need to buy a microfilter, which is installed on every phone in the room.

The main task of the splitter is to separate frequencies - voice (0.3-3.4 kHz) and those used directly by the modem itself (25 kHz-1.5 MHz). It is in this way that the simultaneous operation of the modem and the telephone is ensured, which do not interfere with each other and do not interfere. Splitters are compact and will not cause unnecessary inconvenience. miniature boxEquipped with three connectors and light weight.
ADSL - what is it? Steps for connecting high-speed Internet

- Choose a provider. To date, each provider offers to use this technology. Different types and rates depend on the region, as well as on the technical capabilities of the company, the coverage of which may be limited.
- Purchase of equipment. Currently, it is not necessary to buy a modem, router, router, splitters and microfilters. When drawing up a connection agreement, the provider offers to rent the necessary equipment, including an ADSL modem. In the future, upon termination of the document, the equipment is returned back. The client pays exclusively for the Internet connection. Modern Internet ADSL - what is it? This is a fast, cheap and high-quality way to connect.
- Account activation. For each client, the provider reserves an account, the activation of which can take up to 12 days. However, in most cases, with normal network coverage, the procedure does not require more than a few hours. First, the provider checks the phone number for the possibility of connecting ADSL. If the technology access zone is not enough, then high-speed Internet will not work.
- Equipment setup. At this stage, devices are connected to the telephone line, splitters and microfilters are installed, modem drivers are installed on the computer, and the modem's network parameters are set in the Internet browser.
Pros

What are the advantages of ADSL technology? Here are a few:
- High data rate. ADSL allows you to easily transfer files of any size without a long wait. The technology is constantly being improved, and speeds are growing, significantly expanding the subscriber's capabilities.
- Wireless connection. To use an ADSL system, you do not need to stretch the cable to the subscriber and install a large amount of equipment. Improves network reliability, quality and functionality.
- No interference on the telephone line. The ADSL router operates in independent mode and does not create any problems for the phone to work. You can call and surf the virtual space completely freely.
- Permanent ADSL Internet access. What it is? This means that the network will not fail during operation. The technology does not require reconnection. The user gets access to the Internet constantly and can be online around the clock.
- Reliability and stability. ADSL is the most reliable type of Internet connection today.
- Profitability. The cost of connecting ADSL and installing a modem with a router is minimal and will not hit the family budget.
Flaws
- No crosstalk protection. If several dozen clients are connected to one channel, you won’t have to rely on high speed. The more subscribers on one ADSL, the lower the quality of data transmission.
- ADSL technology has some disadvantages, but they are few. This also includes the minimum speed from the subscriber. The asymmetry of ADSL has an obvious minus - the transfer of files from the subscriber will be long and inconvenient. But the technology is intended, first of all, for quick access to the Internet, for surfing. In addition, the information transmitted from the subscriber takes up a minimum of space and does not require a large resource.
Speed and factors affecting it
ADSL is a high-speed Internet technology, but there is no universal meaning or formula. For each individual subscriber, the speed is individual and is determined by a whole set of factors. Including some of them can affect the reliability and quality of equipment. Therefore, it is best for professionals to install modems and routers.

The main reason for slow ADSL connection speed is the quality of the subscriber line. We are talking about the presence of cable outlets, their condition, the diameter of the wires and the length. Signal attenuation is a direct consequence of increasing the length of the subscriber line, and interference can be reduced by expanding the diameter of the wire. The standard length of an ADSL channel does not exceed 5 km - the optimal range for high-speed data transmission.
Speed characteristics
Compared to other Internet connection technologies, ADSL is much faster in speed. An analog modem will give a maximum of up to 56 Kbps, while ADSL at the dawn of its appearance already allowedtransfer information at speeds up to 144 Kbps.

ADSL-technology, the maximum speed of which is also determined by the characteristics of the modem and can reach 2048 Mbps, optimizes the process of information transfer. Digital lines greatly increase the user experience, taking it beyond the limitations even with multiple connected computers, mobile phones, tablets and other gadgets.
Prospects of technology
The possibilities and resources of ADSL technology are far from exhausted. Even the ADSL2 and ADSL2+ standards, introduced back in the mid-2000s, still retain their relevance and capabilities. This is, in fact, the only technology that can provide wide Internet access without failures and software problems, therefore it is a competitor to many other methods of connecting to the Internet.

Minimum technical equipment is complemented by modern types of modems. Manufacturers annually release new devices designed for continuous operation without the need for maintenance and service. In addition, ADSL speed is constantly growing and is not limited to megabits. The connection becomes relevant both for the home and for the whole office company with several dozen computer clients.
Conclusion
So, we found out what ADSL technology is, what is its essence and principle of operation. As you can see, this is one of those technologies that practically does not fail when working (even inif several dozen users are connected to the network). At the same time, it does not require constant reconnections and speed limits.