The history of telecommunication began with the use of smoking alerts and percussion in Africa, the United States and parts of Asia . In the 1790s, the first set semaphore systems showed up in Europe ; however, it was not until the 1830s that electrical telecom systems began to appear.
Early telecommunications
Early telecoms included smoking alerts and percussion. Talking percussion was used by African residents, New Guinea , and in Southern America . Smoke signals in North America and China . Contrary to what one might think, these techniques were often used to do more than merely announce the presence of a military camp. In 1792, Claude Chappe, a French engineer designed the first visual telegraphy (or semaphore) system between Lille and Paris . A line followed this from Strasbourg to Paris . In 1794, a Swedish engineer, Abraham Edelcrantz designed a different system from Stockholm to Drottningholm. In contrast to Chappe's system, which engaged pulleys spinning supports of wood, Edelcrantz's system relied only on shutters and was therefore faster. However, semaphore as a communication system experienced from the need for skilled operators and expensive towers often at durations of only ten to thirty kilometers (6 to 19 miles). As a result, the last commercial line was stopped in 1880.
Telegraph and Telephone
A beginning research in electrical telegraphy was an 'electrochemical' telegraph created by the German physician, anatomist and inventor Samuel Thomas von Sömmerring in 1809, depending on a previously, less effective design of 1804 by Spanish polymath and scientist Francisco Salva Campillo. Both their designs applied several wires (up to 35) to creatively represent almost all Latin characters and numbers. Thus, messages could be communicated electrically up to a few kilometers (in von Sömmerring's design), with each of the telegraph receiver's wires engrossed in an individual glass tube of acid. The sender through the various wires comprising each digit of a message sequentially applied electricity; at the recipient's end, the currents electrolyzed the acid in the tubes in series, launching sources of hydrogen bubbles next to each associated letter or numeral. The telegraph receiver's operator would creatively observe the bubbles and could then record the transferred message, at the same time at a low baud rate. The major drawback to the system was its beyond reach cost, because of having to produce and string-up the several wire circuit it applied, compared to the single cable (with ground return) used by later telegraphs.
Sir Charles Wheatstone and Sir William Fothergill Cooke made the first commercial electrical telegraph in England . It used deflecting small needles to represent messages and began running over twenty-one kilometers (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 designed a version of the electrical telegraph that he ineffectively showed on 2 September 1837. Soon after, Alfred Vail who designed the register signed him up with — a telegraph terminal that incorporated a signing device for documenting messages to paper tape. This was displayed efficiently over three miles (five kilometers) on 6 January 1838 and gradually over forty miles (sixty-four kilometers) between Washington , D.C.
The first effective transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecom for the first time. Earlier transatlantic cables installed in 1857 and 1858 only managed for several times or even weeks before they failed. The international use of the telegraph has sometimes been known as the "Victorian Internet."
The electrical phone was invented in the 1870s, depending on previously work with harmonic (multisignal) telegraphs. The first commercial phone 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 phone that was needed for such services in both countries. The technological innovation increased quickly from this point, with intercity lines being designed and telephone exchanges in every major city of the United States by the mid-1880s. Despite this, transatlantic voice communication stayed impossible for customers until January 7, 1927 when a connection was recognized using radio. However, no cable connection persisted until TAT-1 was inaugurated on September 25, 1956 providing 36 phone circuits.
In 1880, Bell and co-inventor Charles Sumner Tainter performed the first wireless telephone call with modulated light beams projected by photophones. The scientific ideas of their invention would not be used for several decades, when they were first performed in military and fiber-optic communications.
Radio and Television
Over several years beginning in 1894 the Italian inventor Guglielmo Marconi designed the first complete, from the commercial perspective effective wireless telegraphy system based on airborn electromagnetic waves (radio transmission). In December 1901, he would go on to established wireless communication between Britain and Newfoundland , earning him the Nobel Award in physics in 1909 (which he spread to Karl Braun). In 1900, Reginald Fessenden could easily transfer a human speech wirelessly. On March 25, 1925, Scottish inventor John Logie Baird openly displayed transmitting moving silhouette pictures at the London shopping area Selfridges. In October 1925, Baird was successful in getting moving pictures with halftone colors, which were by most accounts the first true television pictures. This led to a community business presentation of the improved devices on 26 January 1926 again at Selfridges. Baird's first devices relied on the Nipkow disk and thus became known as the mechanical television. It established the basis of semi-experimental broadcast done by the British Broadcasting Corporation beginning September 30, 1929.
For most of the last millennium television relied on the cathode-ray tube invented by Karl Braun. Philo Farnsworth produced the first version of such a television to show guarantee and raw silhouette images were showed to his family on September 7, 1927. Farnsworth's device would contest with the work of Kalman Tihanyi and Vladimir Zworykin. Zworykin's camera, based on Tihanyi's Radioskop, which later would be known as the Iconoscope, had the support of the significant Radio Corporation of America (RCA). In the United States , court action between Farnsworth and RCA would take care of in Farnsworth's favor. John Logie Baird turned from technical television and became an innovator of color television using cathode-ray tubes.
After mid-century, the spread of coaxial cable and microwave radio relay allowed television networks to spread across even huge countries.
Video telephony
The growth of video telephony engaged the traditional growth of several technological innovations, which allowed the use of live video besides voice telecommunications. Video telephony was first made popular in the late 1870s in both the United States and European countries, although the basic sciences to allow its first tests would take nearly a half century to be discovered. This was first embodied in the device which came to be known as video telephone, or videophone, and it progressed from intense analysis and experimentation in several telecommunication fields, especially electrical telegraphy, telephony, radio, and television.
The growth of the important video technology began in the latter half of the 1920s in the United Kingdom and the United States , stimulated especially by John Logie Baird and AT&T's Bell Labs. This happened in, at least by AT&T, to serve as an adjunct adding to the use of the telephone. Various organizations believed that video telephony would be superior to plain voice communications. However, video technology was to be implemented in analogue television broadcasting long before it could become practical—or popular—for videophones.
Video telephony designed in similar with traditional voice telephone systems from the mid-to-late 20th century. Only in the late 20th century with introducing powerful video codec’s and high-speed broadband did it become a practical technology for regular use. With the fast improvements and popularity of the Internet, it became extensive thru the use of videoconferencing and webcams, which often use Internet telephony, and in business, where telepresence technology has helped reduce the need to travel.
Satellite
The first US 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 greetings to the world from US President Dwight D. Eisenhower. In 1960, NASA released 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 released in 1960, was the first active repeater satellite. Satellite nowadays is used for many applications such as uses in GPS, television, Internet and telephone uses.
Telstar was the first active, direct relay commercial communication satellite. That belong to AT&T as part of a multi-national agreement between AT&T, Bell Telephone Labs, NASA, the British General Post Office, and the French National PTT (Post Office) to develop satellite communications, NASA from Cape Canaveral on July 10, 1962, the first privately subsidized space launch, released it. Relay 1 was released on December 13, 1962, and became the first satellite to broadcast across the Pacific on November 22, 1963.
The first and traditionally most essential application for communication satellites was in global long-distance telephony. The fixed Public Switched Telephone Network relays telephone calls from landline phones to an earth station, where they are then sent a receiving satellite dish by means of a geostationary satellite in Earth orbit. Improvements in submarine communications cables, by using fiber optics, caused some decrease in the use of satellites for fixed telephony in the late 20th century, but they still specifically support distant island such as Ascension Island, St. Helena, Diego Garcia, and Easter Island , where no submarine cables are in service. There are also some major continents and some regions of countries where landline telecommunications are unusual to nonexistent, for example Antarctica, plus huge areas of Australia , South America, Africa, Northern Canada, China , Russian and Greenland .
After commercial long-distance telephone service was established by means of communication satellites, a host of other commercial telecoms was also tailored to similar satellites beginning in 1979, such as mobile satellite phones, satellite radio, satellite television, and satellite Internet access. The first adaptation for most such services happened in the 90's as the costs for commercial satellite transponder channels continued to drop significantly.
Computer networks and the Internet
On September 11, 1940, George Stibitz could deliver problems using teletype to his Complicated Number Calculator in New York may and receive the computed results at Dartmouth College in New Hampshire.
These settings of a centralized computer or mainframe with remote foolish terminals stayed well known throughout the 1950s. However, it was not until the Sixties that scientists began to examine packet switching — a technology that would allow sections of data to be sent to different computers without first passes through a central mainframe. A four-node network showed up on December 5, 1969 between the University of California , Los Angeles , the Stanford Research Institute, the University of Utah and the University of California , Florida , Santa Barbarra. This network would become ARPANET, which by 1981 would involve 213 nodes. In June 1973, the first non-US node was added to the network belonging to Norway 's NORSAR project. A node in London soon followed this. ARPANET's growth centered in the Request for Comment procedure and on April 7, 1969, RFC 1 was already published. This procedure is essential because ARPANET would gradually combine with other networks to form the Internet and many of the protocols the Internet is based on nowadays were mentioned through this procedure. In September 1981, RFC 791 presented the Internet protocol v4 (IPv4) and RFC 793 presented the Transmission Control Protocol (TCP) — thus creating the TCP/IP protocol that much of the Online is based on nowadays. A more comfortable transportation protocol that, compared with TCP, did not guarantee the organized distribution of packages called the User Datagram Protocol (UDP) was presented on 28 August 1980 as RFC 768. RFC 821 presented an email protocol, SMTP, in August 1982 and http://1.0 a protocol that would create the hyperlinked Internet possible was presented on May 1996 by RFC 1945.
However not all essential improvements were made through the Request for Comments. Two well-known link methods for local area network (LANs) also showed up in the 70's. Olof Söderblom registered a patent for the Token Ring protocol on October 29, 1974. In addition, John Metcalfe already released a document on the Ethernet protocol and Bob Boggs in the summer 1976 issue of Communications of the ACM.
Internet accessibility became extensive late in the century, using the old telephone and television network.
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