Copyright © Philip M. Parker, INSEAD. Terms of Use.
| Domain | Definition |
Computing | Digital Subscriber Line |
Source: compiled by the editor from various references; see credits. | |
(From Wikipedia, the free Encyclopedia)
Digital Subscriber Line, or DSL, refers to a family of technologies that provide a digital connection over the copper wires of the local telephone network.
As of 2003, DSL provides the principal competition to cable modems for providing high speed Internet access to home consumers.
However, the local loop of copper telephone connections to individual subscribers can usually communicate using a much wider range of frequencies, ranging from these low frequencies up to 200 - 800 kHz, depending on the quality of the circuit and the sophistication of the equipment.
DSL services were devised as a means of overcoming the restriction on the amount of data that could be transmitted over the "voiceband" (see Shannon capacity), by using these additional frequency ranges.
While DSL services often reserve the 0.3 - 4 kHz band for voice calls over the "plain old telephone service" (POTS), the frequencies above and below this range can be used to transmit data.
A DSL connection takes place between equipment of the subscriber and the telephone exchange, with some other protocol used between the exchange and whoever the subscriber really wants to connect to, typically an Internet service provider. This differs from a normal telephone connection, where the public telephone network links subscribers to each other.
In addition the subscriber may need to install a passive electronic filter (known variously as a "splitter" or "filter" or "micro-filter") if using the POTS service on the same line (and possibly also to improve the DSL termination and prevent echoes). This ensures that the DSL modem and the telephone only receive the frequencies they are designed to handle. Subscribers can plug a filter into an existing telephone socket when using a "wires-only" service; or alternatively the DSL provider may install it.
At the exchange a digital subscriber line access multiplexer (DSLAM) terminates the DSL circuits and aggregates them, where they are handed off onto other networking transports. It also separates out the voice component.
DSL implementations may create bridged or routed networks. In a bridged configuration, the group of subscriber computers effectively connect into a single subnet. The earliest implementations used DHCP to provide network details such as the IP address to the subscriber equipment, with authentication via MAC address or an assigned host name. Later implementations often use PPP over ethernet or ATM (PPPoE or PPPoA, also known as PPPoATM), with authentication with a userid and password and using PPP mechanisms to provide network details.
Example DSL technologies (sometimes called xDSL) include:
How it works
When the telephone system was designed, it was intended for voice calls and, for reasons of economy, it was designed to transmit over a frequency range from around 300Hz to 3 to 4kHz (although human speech can range up to around 15kHz, it can easily be understood if limited to this range).Equipment
The subscriber end of the connection consists of a DSL modem. This converts data from the digital electronic pulses used by computers into a digital audio stream of a suitable frequency range for the particular DSL variant in use. Protocols and Configurations
Many DSL technologies implement an ATM layer over the low-level bitstream layer to enable the adaptation of a number of different technologies over the same link.DSL Technologies
The reach-restraints (line length from Central Office to Subscriber) reduce as data rates increase, with technologies like VDSL providing short-range links (typically "fibre to the curb" network scenarios).See also
External links
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Digital Subscriber Line."
Crosswords: DIGITAL SUBSCRIBER LINE |
| Specialty definitions using "DIGITAL SUBSCRIBER LINE": ADSL, Asymmetric Digital Subscriber Line, Asymmetric Digital Subscriber Loop ♦ Carrierless Amplitude/Phase Modulation ♦ Digital Subscriber Line Access Module, Digital Subscriber Loop, DSL, DSLAM ♦ HDSL, High bit-rate Digital Subscriber Line ♦ SDSL, S-HDSL, Single-line Digital Subscriber Line, Single-pair High Speed Digital Subscriber Line ♦ VDSL, Very high bit-rate Digital Subscriber Line ♦ xDSL. (references) |
| Domain | Title |
Books | |
Source: compiled by the editor from various references; see credits. | |
| Subject | Topic | Quote |
Business | As a result, telecom operators have rolled out Asymmetrical Digital Subscriber Line (ADSL) services. (references) | |
France Telecom, as the primary local-loop service provider, intends to switch the entire network into a digital subscriber line over the next few years. (references) | ||
ADSL (Asymmetric Digital Subscriber Line) services were launched by BT in Autumn 2000. Its service, branded "OpenWorld", should allow users to surf the Internet approximately 20 times faster than using a modem. (references) | ||
Economic History | Switzerland | Switzerland will continue to modernize its public networks in ISDN (integrated services, digital networks), DSL (digital subscriber line), broad band communications, and mobile systems. (references) |
Netherlands | In 2000, competition further increased, end-user prices went down, infrastructure investments and the telecom labor market grew and new services were introduced, e.g. ADSL (Asymmetrical Digital Subscriber Line). (references) | |
Uae | It has launched a number of services including Wireless Application Protocol (WAP), internet roaming allowing remote access of home Internet Service Provider (ISP), e-commerce services, and Digital Subscriber Line (DSL) and ISDN for internet and video-conferencing. (references) | |
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
Expressions using "DIGITAL SUBSCRIBER LINE": asymmetric Digital Subscriber Line ♦ digital Subscriber Line Access Module. Additional references. | |
| Source: compiled by the editor from various references; see credits. |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Expression | Frequency per Day |
digital subscriber line | 185 |
high speed digital subscriber line | 16 |
asymmetric digital subscriber line | 3 |
| Source: compiled by the editor from various references; see credits. | |
| Language | Translations for "DIGITAL SUBSCRIBER LINE"; alternative meanings/domain in parentheses. | ||||||||||||||||||||||
Chinese | 數字訂購線路 (DSL). (various references) | ||||||||||||||||||||||
Danish | digital abonnentlinje med stor båndbredde (HDSL, High-bandwidth Digital Subscriber Line), high bit-rate digital subscriber line (HDSL, high bit-rate digital subscriber line), HDSL (HDSL, high bit-rate digital subscriber line, High-bandwidth Digital Subscriber Line). (various references) | ||||||||||||||||||||||
Dutch | high bit-rate digital subscriber line (HDSL, high bit-rate digital subscriber line), HDSL (HDSL, high bit-rate digital subscriber line, High-bandwidth Digital Subscriber Line). (various references) | ||||||||||||||||||||||
Finnish | digitaalinen parikaapelitilaajajohto (HDSL, high bit-rate digital subscriber line), laajakaistainen digitaalinen liittymä (HDSL, High-bandwidth Digital Subscriber Line), HDSL-liittymä (HDSL, High-bandwidth Digital Subscriber Line), HDSL (HDSL, high bit-rate digital subscriber line). (various references) | ||||||||||||||||||||||
French | ligne numérique haut débit (high bit-rate digital subscriber line), HDSL (High-bandwidth Digital Subscriber Line), boucle d'abonné taux binaire élévé (High-bandwidth Digital Subscriber Line). (various references) | ||||||||||||||||||||||
German | digitale Teilnehmerleitung mit hoher Bandbreite (HDSL, High-bandwidth Digital Subscriber Line), digitale Teilnehmeranschluss (HDSL, High-bandwidth Digital Subscriber Line), Teilnehmeranschluss mit hoher Bitrate (HDSL, High-bandwidth Digital Subscriber Line), HDSL (HDSL, High-bandwidth Digital Subscriber Line). (various references) | ||||||||||||||||||||||
Greek | υψίρρυθμη ψηφιακή συνδρομητική γραμμή (HDSL, high bit-rate digital subscriber line). (various references) | ||||||||||||||||||||||
Italian | linea d'abbonato digitale ad elevata ampiezza di banda (HDSL, High-bandwidth Digital Subscriber Line), linea d'abbonato digitale ad alta velocit di trasmissione binaria (HDSL, High-bandwidth Digital Subscriber Line), HDSL (HDSL, High-bandwidth Digital Subscriber Line), Adsl (ADSL, asymetric digital subscriber line, asymetric digital subscriber loop, asymmetric digital subscriber loop). (various references) | ||||||||||||||||||||||
Pig Latin | igitalday ubscribersay inelay linha digital de assinante de elevada largura de banda (HDSL, High-bandwidth Digital Subscriber Line), linha digital de alto desempenho (HDSL, high bit-rate digital subscriber line), linha de assinante digital de alto débito (HDSL, High-bandwidth Digital Subscriber Line), HDSL (HDSL, high bit-rate digital subscriber line, High-bandwidth Digital Subscriber Line). (various references) línea digital de abonado de alta velocidad (HDSL, high bit-rate digital subscriber line), línea digital de abonado a alta velocidad de transmisión (HDSL, high bit-rate digital subscriber line), línea de abonado digital de gran velocidad (HDSL, high bit-rate digital subscriber line), línea de abonado digital de gran ancho de banda (HDSL, High-bandwidth Digital Subscriber Line), HDSL (HDSL, high bit-rate digital subscriber line, High-bandwidth Digital Subscriber Line), bucle de abonado de alta velocidad (HDSL, High-bandwidth Digital Subscriber Line). (various references) digital abonnentledning med stor bandbredd (HDSL, High-bandwidth Digital Subscriber Line), HDSL (HDSL, High-bandwidth Digital Subscriber Line). (various references) | ||||||||||||||||||||||
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "a-b-b-c-d-e-e-g-i-i-i-i-l-l-n-r-r-s-s-t-u" | |
-5 letters: undesirabilities. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
| 1. Crosswords 2. Usage: Commercial 3. Quotations: Non-fiction 4. Expressions | 5. Expressions: Internet 6. Translations: Modern 7. Anagrams 8. Bibliography |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
