# Data link > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Data_link > Markdown URL: https://mediated.wiki/source/Data_link.md > Source: https://en.wikipedia.org/wiki/Data_link > Source revision: 1296744370 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) Means of connecting one location to another in order to transmit information between them This article is about links for digital data transmission. For other uses (including the network layer), see [Data link (disambiguation)](/source/Data_link_(disambiguation)). This article includes a list of references, related reading, or external links, but its sources remain unclear because it lacks inline citations. Please help improve this article by introducing more precise citations. (October 2008) (Learn how and when to remove this message) A **data link** is a means of [connecting one location to another](/source/Telecommunications_link) for the purpose of transmitting and receiving digital information ([data communication](/source/Data_communication)). It can also refer to a set of electronics assemblies, consisting of a transmitter and a receiver (two pieces of [data terminal equipment](/source/Data_terminal_equipment)) and the interconnecting data [telecommunication circuit](/source/Telecommunication_circuit). These are governed by a [link protocol](/source/Link_protocol) enabling digital data to be transferred from a data source to a [data sink](/source/Data_sink). ## Types There are at least three types of basic data-link configurations that can be conceived of and used: - [Simplex communications](/source/Simplex_communication), most commonly meaning all communications in one direction only. - [Half-duplex](/source/Half-duplex) communications, meaning communications in both directions, but not both ways simultaneously. - [Duplex communications](/source/Duplex_(telecommunications)), communications in both directions simultaneously. ## Aviation In civil [aviation](/source/Aviation), a data-link system (known as [Controller Pilot Data Link Communications](/source/Controller_Pilot_Data_Link_Communications)) is used to send information between aircraft and [air traffic controllers](/source/Air_traffic_control) for example when an aircraft is too far from the ATC to make voice radio communication and [radar](/source/Radar) observations possible. Such systems are used for aircraft crossing the [Atlantic](/source/Atlantic), [Pacific](/source/Pacific) and [Indian](/source/Indian_Ocean) oceans. One such system, used by [Nav Canada](/source/Nav_Canada) and [NATS](/source/NATS_Holdings) over the North Atlantic, uses a five-digit data link sequence number confirmed between air traffic control and the pilots of the aircraft before the aircraft proceeds to cross the ocean. This system uses the aircraft's [flight management computer](/source/Flight_management_computer) to send location, speed and altitude information about the aircraft to the ATC. ATC can then send messages to the aircraft regarding any necessary change of course. In [unmanned aircraft](/source/Unmanned_aircraft), land vehicles, boats, and spacecraft, a two-way ([full-duplex](/source/Full-duplex) or [half-duplex](/source/Half-duplex)) data-link is used to send [control signals](/source/Control_system), and to receive [telemetry](/source/Telemetry). ## See also - [ACARS](/source/ACARS) - [NASA Deep Space Network](/source/NASA_Deep_Space_Network) - [Space probe](/source/Space_probe) - [Tactical data link](/source/Tactical_data_link) - [Terminal (telecommunication)](/source/Terminal_(telecommunication)) - [Timex Datalink](/source/Timex_Datalink) - [Unmanned aerial vehicle](/source/Unmanned_aerial_vehicle) ## Sources - This article incorporates [public domain material](/source/Copyright_status_of_works_by_the_federal_government_of_the_United_States) from [*Federal Standard 1037C*](https://web.archive.org/web/20220122224547/https://www.its.bldrdoc.gov/fs-1037/fs-1037c.htm). [General Services Administration](/source/General_Services_Administration). Archived from [the original](https://www.its.bldrdoc.gov/fs-1037/fs-1037c.htm) on 2022-01-22. (in support of [MIL-STD-188](/source/MIL-STD-188)). - This article incorporates [public domain material](/source/Copyright_status_of_works_by_the_federal_government_of_the_United_States) from *[Dictionary of Military and Associated Terms](/source/Department_of_Defense_Dictionary_of_Military_and_Associated_Terms)*. [United States Department of Defense](/source/United_States_Department_of_Defense). v t e Telecommunications History Beacon Broadcasting Cable protection system Cable TV Communications satellite Computer network Data compression audio DCT image video Digital media Internet video online video platform social media streaming Drums Edholm's law Electrical telegraph Fax Heliographs Hydraulic telegraph Information Age Information revolution Internet Mass media Mobile phone Smartphone Optical telecommunication Optical telegraphy Pager Photophone Prepaid mobile phone Radio Radiotelephone Satellite communications Semaphore Phryctoria Semiconductor device MOSFET transistor Smoke signals Telecommunications history Telautograph Telegraphy Teleprinter (teletype) Telephone history The Telephone Cases Television digital streaming Undersea telegraph line Videotelephony Whistled language Wireless revolution Pioneers Nasir Ahmed Edwin Howard Armstrong Mohamed M. Atalla John Logie Baird Paul Baran John Bardeen Alexander Graham Bell Emile Berliner Tim Berners-Lee Francis Blake Jagadish Chandra Bose Charles Bourseul Walter Houser Brattain Vint Cerf Claude Chappe Yogen Dalal Donald Davies Daniel Davis Jr. Amos Dolbear Thomas Edison Philo Farnsworth Reginald Fessenden Lee de Forest Elisha Gray Oliver Heaviside Robert Hooke Erna Schneider Hoover Harold Hopkins Gardiner Greene Hubbard Bob Kahn Dawon Kahng Charles K. Kao Narinder Singh Kapany Hedy Lamarr Roberto Landell Innocenzo Manzetti Guglielmo Marconi Robert Metcalfe Antonio Meucci Samuel Morse Jun-ichi Nishizawa Charles Grafton Page Radia Perlman Alexander Stepanovich Popov Tivadar Puskás Johann Philipp Reis Claude Shannon Almon Brown Strowger Henry Sutton Charles Sumner Tainter Nikola Tesla Camille Tissot Alfred Vail Thomas A. Watson Charles Wheatstone Vladimir K. Zworykin Internet pioneers Transmission media Coaxial cable Fiber-optic communication optical fiber Free-space optical communication Molecular communication Radio waves wireless Transmission line telecommunication circuit Network topology and switching Bandwidth Links Network switching circuit packet Nodes terminal Telephone exchange Multiplexing Space-division Frequency-division Time-division Polarization-division Orbital angular-momentum Code-division Concepts Communication protocol Computer network Data transmission Store and forward Telecommunications equipment Types of network Cellular network Ethernet ISDN LAN Mobile NGN Public Switched Telephone Radio Television Telex UUCP WAN Wireless network Notable networks ARPANET BITNET CYCLADES FidoNet Internet Internet2 JANET NPL network TANet Toasternet Usenet Locations Africa Americas North South Antarctica Asia Europe Oceania Global telecommunications regulation bodies Telecommunication portal Category Outline Commons Authority control databases: National Japan --- Adapted from the Wikipedia article [Data link](https://en.wikipedia.org/wiki/Data_link) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Data_link?action=history)). 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