History of telecommunication

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A replica of one of Claude Chappe's semaphore towers (optical telegraph) in Nalbach, Germany

The history of telecommunication began with the use of smoke signals and drums in Africa, the Americas and parts of Asia. In the 1790s, the first fixed semaphore systems emerged in Europe; however it was not until the 1830s that electrical telecommunication systems started to appear. This article details the history of telecommunication and the individuals who helped make telecommunication systems what they are today. The history of telecommunication is an important part of the larger history of communication.

Summary[edit]

Ancient systems[edit]

Greek hydraulic semaphore systems were used as early as the 4th century BC. The hydraulic semaphores, which worked with water filled vessels and visual signals, functioned as optical telegraphs. However, they could only utilize a very limited range of pre-determined messages, and as with all such optical telegraphs could only be deployed during good visibility conditions.[1]

During the Middle Ages, chains of beacons were commonly used on hilltops as a means of relaying a signal. Beacon chains suffered the drawback that they could only pass a single bit of information, so the meaning of the message such as "the enemy has been sighted" had to be agreed upon in advance. One notable instance of their use was during the Spanish Armada, when a beacon chain relayed a signal from Plymouth to London that signaled the arrival of the Spanish warships.[2]

Further information: Optical communication

Systems since the Middle Ages[edit]

Main article: Semaphore line
A replica of one of Chappe's semaphore towers in Nalbach, Germany

In 1792, Claude Chappe, a French engineer, built the first fixed visual telegraphy system (or semaphore line) between Lille and Paris.[3] However semaphore systems suffered from the need for skilled operators, and expensive towers at intervals of 10–30 kilometers (6–20 mi). As a result of competition from the electrical telegraph, Europe's last commercial semaphore line in Sweden was abandoned in 1880.[4]

Telegraph and telephone[edit]

Experiments on communication with electricity, initially unsuccessful, started in about 1726. Scientists of including Laplace, Ampère, and Gauss were involved. A practical electrical telegraph was proposed in January 1837 by William Fothergill Cooke, who considered it an improvement on the existing "electromagnetic telegraph"; an improved five-needle, six-wire system developed in partnership with Charles Wheatstone entered commercial use in 1838.[5] Early telegraphs used several wires connected to a number of indicator needles.

Businessman Samuel F.B. Morse and physicist Joseph Henry of the United States developed their own, simpler version of the electrical telegraph, independently. Morse successfully demonstrated this system on 2 September 1837. Morse's most important technical contribution to this telegraph was the simple and highly efficient Morse Code co-developed with his associate Alfred Vail, which was an important advance over Wheatstone's more complicated and expensive system, and required just two wires. The communications efficiency of the Morse Code preceded that of the Huffman code in digital communications by over 100 years, but Morse and Vail developed the code purely empirically, with shorter codes for more frequent letters.

The first permanent transatlantic telegraph cable was successfully completed on 27 July 1866, allowing transatlantic electrical communication for the first time.[6] An earlier transatlantic cable had operated for a few months in 1859, and among other things, it carried messages of greeting back and forth between President James Buchanan of the United States and Queen Victoria of the United Kingdom.

However that first transatlantic cable soon failed, and the project to lay a replacement line was delayed for five years by the American Civil War. The first transatlantic telephone cable (which incorporated hundreds of electronic amplifiers) was not operational until 1956, only six years before the first commercial telecommunications satellite, Telstar, was launched into space.[7]

The conventional telephone now in use worldwide was first patented by Alexander Graham Bell in March 1876.[8] That first patent by Bell was the master patent of the telephone, from which all other patents for electric telephone devices and features flowed. Credit for the invention of the electric telephone has been frequently disputed, and new controversies over the issue have arisen from time-to-time. As with other great inventions such as radio, television, the light bulb, and the digital computer, there were several inventors who did pioneering experimental work on voice transmission over a wire, who then improved on each other's ideas. However, the key innovators were Alexander Graham Bell and Gardiner Greene Hubbard, who created the first telephone company, the Bell Telephone Company in the United States, which later evolved into American Telephone & Telegraph (AT&T), at times the world's largest phone company.

The first commercial telephone services were set up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven, Connecticut, and London, England.[9][10]

Radio and television[edit]

The RCA 630-TS, the first mass-produced television set, sold from 1946 to 1947.

In 1832, James Lindsay gave a classroom demonstration of wireless telegraphy via conductive water to his students. By 1854, he was able to demonstrate a transmission across the Firth of Tay from Dundee, Scotland, to Woodhaven, a distance of about two miles (3 km), again using water as the transmission medium.[11] In December 1901, Guglielmo Marconi established wireless communication between St. John's, Newfoundland and Poldhu, Cornwall (England), earning him the Nobel Prize in Physics for 1909, one which he shared with Karl Braun.[12]

On 25 March 1925, John Logie Baird of Scotland was able to demonstrate the transmission of moving pictures at the Selfridge's department store in London, England. Baird's system relied upon the fast-rotating Nipkow disk, and thus it became known as the mechanical television. It formed the basis of experimental broadcasts done by the British Broadcasting Corporation beginning 30 September 1929.[13] However, for most of the 20th century, television systems were designed around the cathode ray tube, invented by Karl Braun. The first version of such an electronic television to show promise was produced by Philo Farnsworth of the United States, and it was demonstrated to his family in Idaho on 7 September 1927.[14]

Television, however, is not solely a technology, limited to its basic and practical application. It functions both as an appliance, and also as a means for social story telling and message dissemination. It is a cultural tool that provides a communal experience of receiving information and experiencing fantasy. It acts as a “window to the world” by bridging audiences from all over through programming of stories, triumphs, and tragedies that are outside of personal experiences.[15]

Videotelephony[edit]

The 1969 AT&T Mod II Picturephone, the result of decades long R&D at a cost of over $500M

The development of videotelephony involved the historical development of several technologies which enabled the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its very earliest trials would take nearly a half century to be discovered. This was first embodied in the device which came to be known as the video telephone, or videophone, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, and television.

The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs. This occurred in part, at least by AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications. However video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones.

Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Only in the late 20th century with the advent of powerful video codecs and high-speed broadband did it become a practical technology for regular use. With the rapid improvements and popularity of the Internet, it became widespread through the use of videoconferencing and webcams, which frequently utilize Internet telephony, and in business, where telepresence technology has helped reduce the need to travel.

Satellite[edit]

The first U.S. satellite to relay communications was Project SCORE in 1958, which used a tape recorder to store and forward voice messages. It was used to send a Christmas greeting to the world from U.S. President Dwight D. Eisenhower. In 1960 NASA launched an Echo satellite; the 100-foot (30 m) aluminized PET film balloon served as a passive reflector for radio communications. Courier 1B, built by Philco, also launched in 1960, was the world's first active repeater satellite.

A Hungarian stamp depicting two Telstar satellites relaying telecommunication signals between Earth stations

Telstar was the first active, direct relay commercial communications satellite. Belonging to AT&T as part of a multi-national agreement between AT&T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT (Post Office) to develop satellite communications, it was launched by NASA from Cape Canaveral on 10 July 1962, the first privately sponsored space launch. Relay 1 was launched on 13 December 1962, and became the first satellite to broadcast across the Pacific on 22 November 1963.[16]

The first and historically most important application for communication satellites was in intercontinental long distance telephony. The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted to a receiving satellite dish via a geostationary satellite in Earth orbit. Improvements in submarine communications cables, through the use of fiber-optics, caused some decline in the use of satellites for fixed telephony in the late 20th century, but they still exclusively service remote islands such as Ascension Island, Saint Helena, Diego Garcia, and Easter Island, where no submarine cables are in service. There are also some continents and some regions of countries where landline telecommunications are rare to nonexistent, for example Antarctica, plus large regions of Australia, South America, Africa, Northern Canada, China, Russia and Greenland.

After commercial long distance telephone service was established via communication satellites, a host of other commercial telecommunications were also adapted to similar satellites starting in 1979, including mobile satellite phones, satellite radio, satellite television and satellite Internet access. The earliest adaption for most such services occurred in the 1990s as the pricing for commercial satellite transponder channels continued to drop significantly.

Digital cinema[edit]

Main article: Digital cinema

Realization and demonstration, on October 29, 2001, of the first digital cinema transmission by satellite in Europe[17][18][19] of a feature film by Bernard Pauchon[20] and Philippe Binant.[21]

Computer networks and the Internet[edit]

On 11 September 1940, George Stibitz was able to transmit problems using teleprinter to his Complex Number Calculator in New York and receive the computed results back at Dartmouth College in New Hampshire.[22] This configuration of a centralized computer or mainframe computer with remote "dumb terminals" remained popular throughout the 1950s and into the 1960s. However, it was not until the 1960s that researchers started to investigate packet switching — a technology that allows chunks of data to be sent between different computers without first passing through a centralized mainframe. A four-node network emerged on 5 December 1969. This network soon became the ARPANET, which by 1981 would consist of 213 nodes.[23]

ARPANET's development centred on the Request for Comment process and on 7 April 1969, RFC 1 was published. This process is important because ARPANET would eventually merge with other networks to form the Internet, and many of the communication protocols that the Internet relies upon today were specified through the Request for Comment process. In September 1981, RFC 791 introduced the Internet Protocol version 4 (IPv4) and RFC 793 introduced the Transmission Control Protocol (TCP) — thus creating the TCP/IP protocol that much of the Internet relies upon today.

However, not all important developments were made through the Request for Comment process. Two popular link protocols for local area networks (LANs) also appeared in the 1970s. A patent for the token ring protocol was filed by Olof Soderblom on 29 October 1974, and a paper on the Ethernet protocol was published by Robert Metcalfe and David Boggs in the July 1976 issue of Communications of the ACM.[24][25] The Ethernet protocol had been inspired by the ALOHAnet protocol which had been developed by electrical engineering researchers at the University of Hawaii.

Early telecommunications[edit]

Main articles: Beacon and Optical telegraphy

Early telecommunications included smoke signals and drums. Talking drums were used by natives in Africa, New Guinea and South America, and smoke signals in North America and China. Contrary to what one might think, these systems were often used to do more than merely announce the presence of a military camp.[26][27]

In 1792, a French engineer, Claude Chappe built the first visual telegraphy (or semaphore) system between Lille and Paris. This was followed by a line from Strasbourg to Paris. In 1794, a Swedish engineer, Abraham Edelcrantz built a quite different system from Stockholm to Drottningholm. As opposed to Chappe's system which involved pulleys rotating beams of wood, Edelcrantz's system relied only upon shutters and was therefore faster.[28] However semaphore as a communication system suffered from the need for skilled operators and expensive towers often at intervals of only ten to thirty kilometres (six to nineteen miles). As a result, the last commercial line was abandoned in 1880.[29]

Telegraph and telephone[edit]

Stock telegraph ticker machine by Thomas Edison

A very early experiment in electrical telegraphy was an 'electrochemical' telegraph created by the German physician, anatomist and inventor Samuel Thomas von Sömmerring in 1809, based on an earlier, less robust design of 1804 by Spanish polymath and scientist Francisco Salva Campillo.[30] Both their designs employed multiple wires (up to 35) in order to visually represent almost all Latin letters and numerals. Thus, messages could be conveyed electrically up to a few kilometers (in von Sömmerring's design), with each of the telegraph receiver's wires immersed in a separate glass tube of acid. An electrical current was sequentially applied by the sender through the various wires representing each digit of a message; at the recipient's end the currents electrolysed the acid in the tubes in sequence, releasing streams of hydrogen bubbles next to each associated letter or numeral. The telegraph receiver's operator would visually observe the bubbles and could then record the transmitted message, albeit at a very low baud rate.[30] The principal disadvantage to the system was its prohibitive cost, due to having to manufacture and string-up the multiple wire circuits it employed, as opposed to the single wire (with ground return) used by later telegraphs.

The first commercial electrical telegraph was constructed in England by Sir Charles Wheatstone and Sir William Fothergill Cooke. It used the deflection of needles to represent messages and started operating over twenty-one kilometres (thirteen miles) of the Great Western Railway on 9 April 1839. Both Wheatstone and Cooke viewed their device as "an improvement to the [existing] electromagnetic telegraph" not as a new device.

On the other side of the Atlantic Ocean, Samuel Morse independently developed a version of the electrical telegraph that he unsuccessfully demonstrated on 2 September 1837. Soon after he was joined by Alfred Vail who developed the register — a telegraph terminal that integrated a logging device for recording messages to paper tape. This was demonstrated successfully over three miles (five kilometres) on 6 January 1838 and eventually over forty miles (sixty-four kilometres) between Washington, D.C. and Baltimore on 24 May 1844. The patented invention proved lucrative and by 1851 telegraph lines in the United States spanned over 20,000 miles (32,000 kilometres).[31]

The first successful transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecommunication for the first time. Earlier transatlantic cables installed in 1857 and 1858 only operated for a few days or weeks before they failed.[32] In the modern era, the international use of the telegraph has sometimes been dubbed the "Victorian Internet".[33]

The electric telephone was invented in the 1870s, based on earlier work with harmonic (multi-signal) telegraphs. The first commercial telephone services were set up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London. Alexander Graham Bell held the master patent for the telephone that was needed for such services in both countries. The technology grew quickly from this point, with inter-city lines being built and telephone exchanges in every major city of the United States by the mid-1880s.[34][35][36] Despite this, transatlantic voice communication remained impossible for customers until January 7, 1927 when a connection was established using radio. However no cable connection existed until TAT-1 was inaugurated on September 25, 1956 providing 36 telephone circuits.[37]

In 1880, Bell and co-inventor Charles Sumner Tainter conducted the world's first wireless telephone call via modulated lightbeams projected by photophones. The scientific principles of their invention would not be utilized for several decades, when they were first deployed in military and fiber-optic communications.

Radio and television[edit]

Over several years starting in 1894 the Italian inventor Guglielmo Marconi built the first complete, commercially successful wireless telegraphy system based on airborn electromagnetic waves (radio transmission).[38] In December 1901, he would go on to established wireless communication between Britain and Newfoundland, earning him the Nobel Prize in physics in 1909 (which he shared with Karl Braun).[39] In 1900 Reginald Fessenden was able to wirelessly transmit a human voice. On March 25, 1925, Scottish inventor John Logie Baird publicly demonstrated the transmission of moving silhouette pictures at the London department store Selfridges. In October 1925, Baird was successful in obtaining moving pictures with halftone shades, which were by most accounts the first true television pictures.[40] This led to a public demonstration of the improved device on 26 January 1926 again at Selfridges. Baird's first devices relied upon the Nipkow disk and thus became known as the mechanical television. It formed the basis of semi-experimental broadcasts done by the British Broadcasting Corporation beginning September 30, 1929.

For most of the twentieth century televisions depended upon the cathode ray tube invented by Karl Braun. The first version of such a television to show promise was produced by Philo Farnsworth and crude silhouette images were demonstrated to his family on September 7, 1927. Farnsworth's device would compete with the concurrent work of Kalman Tihanyi and Vladimir Zworykin. Though the execution of the device was not yet what everyone hoped it could be, it earned Farnsworth a small production company. In 1934, he gave the first public demonstration of the television at Philadelphia's Franklin Institute and opened his own broadcasting station.[41] Zworykin's camera, based on Tihanyi's Radioskop, which later would be known as the Iconoscope, had the backing of the influential Radio Corporation of America (RCA). In the United States, court action between Farnsworth and RCA would resolve in Farnsworth's favour.[42] John Logie Baird switched from mechanical television and became a pioneer of colour television using cathode-ray tubes.[40]

After mid-century the spread of coaxial cable and microwave radio relay allowed television networks to spread across even large countries.

Videotelephony[edit]

The 1969 AT&T Mod II Picturephone, the result of decades long R&D at a cost of over $500M.

The development of videotelephony involved the historical development of several technologies which enabled the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its very earliest trials would take nearly a half century to be discovered. This was first embodied in the device which came to be known as the video telephone, or videophone, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, and television.

The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs. This occurred in part, at least by AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications. However video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones.

Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Only in the late 20th century with the advent of powerful video codecs and high-speed broadband did it become a practical technology for regular use. With the rapid improvements and popularity of the Internet, it became widespread thru the use of videoconferencing and webcams, which frequently utilize Internet telephony, and in business, where telepresence technology has helped reduce the need to travel.

Satellite[edit]

The first U.S. satellite to relay communications was Project SCORE in 1958, which used a tape recorder to store and forward voice messages. It was used to send a Christmas greeting to the world from U.S. President Dwight D. Eisenhower. In 1960 NASA launched an Echo satellite; the 100-foot (30 m) aluminized PET film balloon served as a passive reflector for radio communications. Courier 1B, built by Philco, also launched in 1960, was the world's first active repeater satellite. Satellites these days are used for many applications such as uses in GPS, television, internet and telephone uses.

A Hungarian stamp depicting two Telstar satellites relaying telecommunication signals between Earth stations.

Telstar was the first active, direct relay commercial communications satellite. Belonging to AT&T as part of a multi-national agreement between AT&T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT (Post Office) to develop satellite communications, it was launched by NASA from Cape Canaveral on July 10, 1962, the first privately sponsored space launch. Relay 1 was launched on December 13, 1962, and became the first satellite to broadcast across the Pacific on November 22, 1963.[16]

The first and historically most important application for communication satellites was in intercontinental long distance telephony. The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted a receiving satellite dish via a geostationary satellite in Earth orbit. Improvements in submarine communications cables, through the use of fiber-optics, caused some decline in the use of satellites for fixed telephony in the late 20th century, but they still exclusively service remote islands such as Ascension Island, Saint Helena, Diego Garcia, and Easter Island, where no submarine cables are in service. There are also some continents and some regions of countries where landline telecommunications are rare to nonexistent, for example Antarctica, plus large regions of Australia, South America, Africa, Northern Canada, China, Russia and Greenland.

After commercial long distance telephone service was established via communication satellites, a host of other commercial telecommunications were also adapted to similar satellites starting in 1979, including mobile satellite phones, satellite radio, satellite television and satellite Internet access. The earliest adaption for most such services occurred in the 1990s as the pricing for commercial satellite transponder channels continued to drop significantly.

Computer networks and the Internet[edit]

Main articles: Computer Networking -History and History of the Internet

On September 11, 1940, George Stibitz was able to transmit problems using teletype to his Complex Number Calculator in New York and receive the computed results back at Dartmouth College in New Hampshire.[43] This configuration of a centralized computer or mainframe with remote dumb terminals remained popular throughout the 1950s. However it was not until the 1960s that researchers started to investigate packet switching — a technology that would allow chunks of data to be sent to different computers without first passing through a centralized mainframe. A four-node network emerged on December 5, 1969 between the University of California, Los Angeles, the Stanford Research Institute, the University of Utah and the University of California, Santa Barbara. This network would become ARPANET, which by 1981 would consist of 213 nodes.[44] In June 1973, the first non-US node was added to the network belonging to Norway's NORSAR project. This was shortly followed by a node in London.[45]

ARPANET's development centred on the Request for Comment process and on April 7, 1969, RFC 1 was published. This process is important because ARPANET would eventually merge with other networks to form the Internet and many of the protocols the Internet relies upon today were specified through this process. In September 1981, RFC 791 introduced the Internet Protocol v4 (IPv4) and RFC 793 introduced the Transmission Control Protocol (TCP) — thus creating the TCP/IP protocol that much of the Internet relies upon today. A more relaxed transport protocol that, unlike TCP, did not guarantee the orderly delivery of packets called the User Datagram Protocol (UDP) was submitted on 28 August 1980 as RFC 768. An e-mail protocol, SMTP, was introduced in August 1982 by RFC 821 and http://1.0 a protocol that would make the hyperlinked Internet possible was introduced on May 1996 by RFC 1945.

However not all important developments were made through the Request for Comment process. Two popular link protocols for local area networks (LANs) also appeared in the 1970s. A patent for the Token Ring protocol was filed by Olof Söderblom on October 29, 1974.[46] And a paper on the Ethernet protocol was published by Robert Metcalfe and David Boggs in the July 1976 issue of Communications of the ACM.[47]

Internet access became widespread late in the century, using the old telephone and television networks.

Timelines[edit]

Timeline of communication tools, 2014 update..jpg

Distance telecommunications[edit]

Visual, auditory and ancillary methods (non-electrical):


Basic electrical signals:


Advanced electrical and electronic signals:


See also[edit]

References[edit]

  1. ^ Lahanas, Michael, Ancient Greek Communication Methods, Mlahanas.de website. Retrieved 14 July 2009.
  2. ^ David Ross, The Spanish Armada, Britain Express, October 2008.
  3. ^ Les Télégraphes Chappe, Cédrick Chatenet, l'Ecole Centrale de Lyon, 2003.
  4. ^ CCIT/ITU-T 50 Years of Excellence, International Telecommunication Union, 2006.
  5. ^ The Electromagnetic Telegraph, J. B. Calvert, 19 May 2004.
  6. ^ The Atlantic Cable, Bern Dibner, Burndy Library Inc., 1959
  7. ^ Arthur C. Clarke. Voice Across the Sea, Harper & Brothers, New York City, 1958.
  8. ^ Brown, Travis (1994). Historical first patents: the first United States patent for many everyday things (illustrated ed.). University of Michigan: Scarecrow Press. p. 179. ISBN 978-0-8108-2898-8. 
  9. ^ Connected Earth: The telephone, BT, 2006.
  10. ^ History of AT&T, AT&T, 2006.
  11. ^ Dundee City Council. Biography: James Bowman Lindsay 1799 – 1862, Macdonald Black, Dundee City Council website. Retrieved 9 September 2010.
  12. ^ Tesla Biography, Ljubo Vujovic, Tesla Memorial Society of New York, 1998.
  13. ^ The Pioneers, MZTV Museum of Television, 2006.
  14. ^ Philo Farnsworth, Neil Postman, TIME Magazine, 29 March 1999.
  15. ^ Lotz, Amanda (2007). The Television Will Be Revolutionized. New York and London: New York University Press. p. 3. ISBN 978-0-8147-5220-3. 
  16. ^ a b "Significant Achievements in Space Communications and Navigation, 1958–1964". NASA-SP-93. NASA. 1966. pp. 30–32. Retrieved 31 October 2009. 
  17. ^ France Télécom, Commission Supérieure Technique de l'Image et du Son, Communiqué de presse, Paris, October 29th, 2001.
  18. ^ «Numérique : le cinéma en mutation», Projections, 13, CNC, Paris, September 2004, p. 7.
  19. ^ Olivier Bomsel, Gilles Le Blanc, Dernier tango argentique. Le cinéma face à la numérisation, Ecole des Mines de Paris, 2002, p. 12.
  20. ^ Bernard Pauchon, France Telecom and digital cinema, ShowEast, 2001, p. 10.
  21. ^ Première numérique pour le cinéma français, 01net, 2002.
  22. ^ George Stlibetz, Kerry Redshaw, 1996.
  23. ^ Hafner, Katie (1998). Where Wizards Stay Up Late: The Origins Of The Internet. Simon & Schuster. ISBN 0-684-83267-4. 
  24. ^ Data transmission system, Olof Solderblom, PN 4,293,948, October 1974.
  25. ^ Ethernet: Distributed Packet Switching for Local Computer Networks, Robert M. Metcalfe and David R. Boggs, Communications of the ACM (pp 395–404, Vol. 19, No. 5), July 1976.
  26. ^ Native American Smoke Signals, William Tomkins, 2005.
  27. ^ Talking Drums, Instrument Encyclopedia, Cultural Heritage for Community Outreach, 1996.
  28. ^ Les Télégraphes Chappe, Cédrick Chatenet, l'Ecole Centrale de Lyon, 2003.
  29. ^ CCIT/ITU-T 50 Years of Excellence, International Telecommunication Union, 2006.
  30. ^ a b Jones, R. Victor Samuel Thomas von Sömmerring's "Space Multiplexed" Electrochemical Telegraph (1808-10), Harvard University website. Attributed to "Semaphore to Satellite" , International Telecommunication Union, Geneva 1965. Retrieved 2009-05-01
  31. ^ The Electromagnetic Telegraph, J. B. Calvert, April 2000.
  32. ^ The Atlantic Cable, Bern Dibner, Burndy Library Inc., 1959
  33. ^ Martin Redfern, Wiring up the 'Victorian internet', BBC News, 29 November 2005.
  34. ^ Connected Earth: The telephone, BT, 2006.
  35. ^ History of AT&T, AT&T, 2006.
  36. ^ Page, Arthur W. (January 1906). "Communication By Wire And "Wireless": The Wonders of Telegraph and Telephone". The World's Work: A History of Our Time XIII: 8408–8422. Retrieved 2009-07-10. 
  37. ^ History of the Atlantic Cable & Submarine Telegraphy, Bill Glover, 2006.
  38. ^ Icons of invention: the makers of the modern world from Gutenberg to Gates. ABC-CLIO. Retrieved 07-08-2011.  Check date values in: |accessdate= (help)
  39. ^ Tesla Biography, Ljubo Vujovic, Tesla Memorial Society of New York, 1998.
  40. ^ a b The Baird Television Website
  41. ^ Karwatka, D. (1996). Philo Farnsworth--television pioneer. Tech Directions, 56(4), 7.
  42. ^ Philo Farnsworth, Neil Postman, TIME Magazine, 29 March 1999
  43. ^ George Stibitz, Kerry Redshaw, 1996.
  44. ^ Hafner, Katie (1998). Where Wizards Stay Up Late: The Origins Of The Internet. Simon & Schuster. ISBN 0-684-83267-4. 
  45. ^ NORSAR and the Internet: Together since 1973, NORSAR, 2006.
  46. ^ Data transmission system, Olof Soderblom, PN 4,293,948, October 1974.
  47. ^ Ethernet: Distributed Packet Switching for Local Computer Networks, Robert M. Metcalfe and David R. Boggs, Communications of the ACM (pp. 395-404, Vol. 19, No. 5), July 1976.

Further reading[edit]

  • Hilmes, Michele. Network Nations: A Transnational History of American and British Broadcasting (2011)
  • John, Richard. Network Nation: Inventing American Telecommunications (Harvard U.P. 2010), emphasis on telephone
  • Noll, Michael. The Evolution of Media, 2007, Rowman & Littlefield
  • Poe, Marshall T. A History of Communications: Media and Society From the Evolution of Speech to the Internet (Cambridge University Press; 2011) 352 pages; Documents how successive forms of communication are embraced and, in turn, foment change in social institutions.
  • Wheen, Andrew. DOT-DASH TO DOT.COM: How Modern Telecommunications Evolved from the Telegraph to the Internet (Springer, 2011)
  • Wu, Tim. The Master Switch: The Rise and Fall of Information Empires (2010)

External links[edit]