History of videotelephony | Wikipedia audio article

History of videotelephony | Wikipedia audio article

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The history of video telephony covers. The historical. Development of several technologies which, enable, the use of live video in addition to voice, telecommunications. The, concept. Of video telephony 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 Bell, Labs, this. Occurred in part at least with AT&T, to serve as an adjunct supplementing. The use of the telephone a number. Of organizations. Believed that video telephony 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 video phones, video. Telephony developed. In parallel with, conventional. Voice telephone, systems, from the mid to late 20th, century, very. Expensive, video conferencing. Systems, rapidly, evolved, throughout the 1980s. And 1990s, from. Proprietary equipment, software. And network requirements. To standards-based, technologies. That were readily available to, the general public at a reasonable, cost only. In the late 20th, century with, the advent of powerful, video codecs, combined, with high-speed Internet broadband. And ISDN, service. Did video telephony become. A practical. Technology. For regular, use, with. The rapid improvements. And popularity. Of the internet video. Telephony has, become widespread through, the deployment of video enabled mobile phones, plus video conferencing. And computer, webcams, which utilize, Internet, telephony in the. Upper echelon, of government, business, and commerce telepresence. Technology and advanced, former video conferencing. Has helped reduce the need to travel. Topic. Early, history. Barely. Two years after, the telephone was first patented in the United, States in, 1876. By dr., Alexander. Graham Bell an early, concept, of a combined, video phone and widescreen, television. Called a telephone a scope was conceptualized. In the popular, periodicals of, the day it. Was also mentioned in various early science, fiction, works such as living taim circle la, vie electric the 20th century. The electrical, life and other works written by Albert Robbie de and was also sketched, in various, cartoons, by George du Maurier as a fictional, invention, of Thomas Edison, one. Such sketch was published, on December, 9th, 1878. In punch magazine the term electroscope. Was also used in 1878. By French writer and publisher Louis Figgy heir to popularize, an invention wrongly, interpreted as, real and incorrectly, ascribed, to dr. Bell possibly, after his Volta laboratory, discreetly, deposited, a sealed container of, a Graphophone, phonograph. At the Smithsonian. Institution. For safekeeping. Written. Under the pseudonym. Electrician. One. Article, earlier claimed, that an eminent. Scientist. Had. Invented a device whereby, objects, or people anywhere, in the world. Could. Be seen anywhere by anybody. The. Device among, other functions would, allow merchants, to transmit, pictures of their wares to their customers, and the contents, of museum, collections, to be made available to, scholars in distant, cities. Quote. In the era prior, to the advent of broadcasting. Electrical. Seeing. Devices. Were conceived, as adjuncts, to the telephone, thus creating, the concept of a videophone fraudulent.

Reports, Of amazing, advances. In video telephones. Would be publicized, as early as 1880. And would reoccur, every, few years such, as the episode, of doctor. Sylvester. Of Paris, who claimed in 1902. To have invented, a powerful, and inexpensive. Video telephone. Termed, that spectrograph, the intellectual. Property, rights he believed were worth five million dollars, after. Reviewing. His claim dr., Bell denounced. The supposed, invention. As a. Fairy. Tale and publicly. Commented, on the charlatans, promoting. Bogus, inventions. For financial. Gain or self-promotion. However, dr., Alexander. Graham Bell personally. Thought that video telephony was, achievable, even, though his contributions. To its advancement, were incidental. In. April, 1891. Dr.. Bell actually did record, conceptual. Notes on an electrical. Radio phone which discussed, the possibility. Of. Seeing. By electricity, using, devices that employed tellurium, or selenium imaging, components. Bell. Wrote decades, prior to the invention of the image dissector. Should. It be found. That. The image sensor is illuminated. Then an apparatus, might, be constructed. In which each piece of selenium, is a mere speck like the head of a small pin the smaller the better the. Darkened, selenium, should be placed in a cup-like receiver, which can fit over the eye. Then. When the first selenium, speck is presented, to an illuminated. Object it may be possible that the eye in the darkened receiver should perceive, not merely light but an image of the object. Bell. Went on to later predict, that. Dots. A day would come when the man at the telephone would be able to see the distant, person to whom he was speaking. The. Discoveries. In physics chemistry, and materials. Science, underlying, video technology. Would not be in place until the mid 1920s, first. Being utilized, in electromechanical, television. More. Practical, all electronic, video and television would not emerge until 1939.

But, Would then suffer, several, more years of delays before gaining popularity due. To the onset, and effects of World War 2 the, compound. Name videophone. Slowly, entered, into general usage after nine 10:50, although, video telephone, likely, entered the lexicon earlier, after video was coined in, 1935. Prior. To that time there appeared to be no standard, terms for video telephone, with expressions, such as sight sound television system. Visual, radio and nearly 20 others in English, being used to describe the marriage of telegraph, telephone, television. And radio technologies. Employed, in early experiments. Among the technological. Precursors. To the videophone were, telegraphic. Image transmitters. Created, by several companies such, as the wire photo used, by Western, Union and the tele Osteria graph developed, by AT&T, Bell. Labs which were forerunners of today's fax, facsimile, machines. Such. Early image transmitters. Were themselves, based on previous, work by Ernest, Hummel and others in the 19th, century, by. 1927. AT&T. Had created, its earliest electromechanical. Television. Video, phone called the Econo phone from greek image, sound which operated, at 18 frames per second, and occupied, half a room full of equipment cabinets. An early. Us test in 1927. Had, there then Commerce, Secretary Herbert. Hoover addressed an audience in, New York City from Washington, DC, although the audio portion, was two-way the video portion was one-way with only those in New York being able to see Hoover, by. 1938. He and T's two-way, television, telephone system. Was in full-scale, experimental. Use the. Bell Labs Manhattan. Facility, devoted, years of research, to it during the 1930s. Led by dr. Herbert Ives along with his team of more than 200. Scientists, engineers and, technicians, intending. To develop, it for both telecommunication. And broadcast, entertainment. Purposes, there were also other public, demonstrations. Of two-way, television, telephone, systems. During, this period by inventors, and entrepreneurs who. Sought to compete with AT&T, although. None appeared capable, of dealing with the technical issues of signal, compression, that Bell Labs would eventually, resolve. Signal. Compression, and it's later sibling, data compression, were fundamental. The issue of transmitting. The very large bandwidth, of low resolution black, and white video through, the very limited, capacity, of low-speed copper, PSTN. Telephone, lines higher resolution. Color video phones, would require even far greater capabilities. After. The Second World War, Bell Labs resumed, its efforts during the 1950s. And 1960s, eventually. Leading to a TNT's, picture, phone. Topic. World's. First public video phone service, Germany. 1936. To, 1940. In. Early, 1936. The world's first public video, telephone, service, Germany's, gegen Sen phone sprechen, lagan visual, telephone, system, was developed by doctor Georg Schubert, who headed the development, department at the furniture AG a Technical, combined for television, broadcasting.

Technology. It. Was opened, by the German, Reich sposed post office, between Berlin, and Leipzig, utilizing. Broadband, coaxial. Cable, to cover the distance of approximately. 160. Kilometers 100. Miles. Schubert. System, was based on Gunther Kerr winkles earlier research of, the late 1920s. That he displayed at the 1929. International. Fung castellón Berlin Berlin international. Radio exposition. Schubert's. Higher performance, system, employed, mechanical. Television scanning. And 20 centimeters 8-inch. Square displays, with a resolution of, 180. Lines initially. 150. Lines transmitting. Some 40,000. Pixels per frame at, 25, frames per second. The. System's opening, was inaugurated by, the minister of post Paul von eltz Rubinek in Berlin on March 1st. 1936. Who viewed and spoke with leipzig, chief burgomaster, it. Employed, a nip car disc flying spot, scanner for its transmitter, and a cathode ray display, tube with an initial, resolution. Of 150. Lines at its receiving, end video phone booth the. Same coaxial. Cables, were also, used to distribute television. Programming. In. The initial service trial, broadband, coaxial. Cable, lines initially, linked Berlin to Leipzig. After. A period of experimentation the. System, entered public use and was soon extended another, 160. Kilometers, 100. Miles from Berlin to Hamburg, and then in July 1938. From Leipzig to Nuremberg and Munich the. System, eventually operated. With more than one, and kilometers. 620. Miles of coaxial. Cable, transmission, lines, the. Video phones were integrated. Within large public, video phone booths with two booths provided. Per city, calls. Between Berlin and Leipzig, cost RM three one half approximately. One-sixth. Of a British Pound Sterling or about one fifteenth, of the average weekly wage, the. Video telephone, equipment, used in Berlin was designed, and built by the German, post office laboratory. Video. Phone equipment used, in other German, cities were developed, by furniture AG, partly, owned by Baird Television, limited of the UK inventors, of the world's first functional, television. During. Its life the German system underwent further development. And testing, resulting, in higher resolutions. And a conversion, to an all-electronic, camera, tube transmission. System, to replace its mechanical, nip cow scanning, disc while. The system's image quality was primitive by modern standards it was deemed impressive, in contemporary, reports of the era with users able to clearly discern the hands-on wristwatches, the special, public video phone service, was offered to the general public which had to visit special, post office Furness, prek Stellan video telephone, booths from far. Side speech place, simultaneously.

In. Their respective cities but, which at the same time also had Nazi, political and propagandistic, overtones, similar, to the broadcasting. Of the 1936. Olympic, Games in Berlin, the. German post office, announced ambitious, plans to extend their public videophone, network to Cologne Frankfurt. And Vienna Austria, but. Expansion, plans were discontinued. In 1939. With the start of the Second World War. After. Germany subsequently. Became fully engaged, in the war its public, videophone system, was closed in 1940. With its expensive, intercity broadband, cables, converted, to telegraphic, message traffic and broadcast, television service. A similar, commercial post, office system, was also created, in France during, the late 1930s. The. Deutsche, Bundespost Postal. Service, would decades, later develop, and ploy it's b.i.g, Fon, broadband, integrated. Glass fiber optical, network video telephony network, from 1981. To 1988. Serving. Several large German, cities and also, created, one of Europe's first public, switched broadband, services, in 1989. Topic. AT&T. Picture phone, 1964. In the United, States AT&T. Bell Labs conducted. Extensive research, and development, of video phones, eventually. Leading to public demonstrations. Of its trademarked, picture phone product, and service, in the 1960s. Its. Large Manhattan, experimental. Laboratory devoted. Years of technical, research during, the 1930s. Led by dr. Herbert Ives along with his team of more than 200. Scientists, engineers and, technicians. The. Bell Labs early experimental, model, of 1930. Had transmitted. Uncompressed, video through, multiple, phone lines a highly impractical and, expensive method. Unsuitable, for commercial, use during, the mid-1950s. Its laboratory. Work had produced, another early test prototype, capable, of transmitting still, images, every two seconds, over regular, analog PSTN. Telephone, lines, the. Images, were captured by the picture, phones compact, vidicon, camera, and then transferred, to a storage, tube or magnetic, drum for transmission. Over regular, phone lines at two-second, intervals to, the receiving, unit which display, them on a small cathode, ray television. Tube. AT&T. Had earlier promoted, its experimental, video for, telephone, service, at the 1939. New York World's Fair, the more advanced, picture phone models, early promotion, included, public evaluation displays. At Disneyland, and the 1964. New York World's Fair with, the first transcontinental, video. Call between the two venues made, on April 20th. 1964. The. First picture, phone model model number one demonstration. Units used small oval housings, on swivel stands, intended, to stand on desks. Similar. AT&T. Picture phone units, were also featured at the telephone pavilion, also, called the Bell Telephone, at Expo, 67 an, International, World's Fair held in Montreal Canada, in. 1967. Demonstration. Units were available at the fairs for the public to test with Faygo is permitted, to make video phone calls to volunteer, recipients. At other locations. AT&T. S advanced, mod to picture-phone. 1969. The United States would not see its first public, video phone booths until. 1964. When AT&T installed. Their earliest commercial videophone. Units the picture phone ma died in booths that were set up in New York's Grand Central, Terminal Washington. DC and Chicago. Its. System, was the result of decades of research and development at Bell Labs its principal. Supplier Western, Electric plus other researchers, working under contract, to the Bell Labs, however. The use of reservation. Time slots and their cost of $16. Washington, DC to New York to $27.00. New York to Chicago equivalent. To 118. Dollars to $200. In 2012. Dollars, for a three-minute call at the public video phone booths greatly, limited, their appeal resulting, in their closure by, 1968. Picture, phones were also, later installed, in the offices, of Westinghouse, and Alcoa in Pittsburgh, as well as other technology. Companies in that city, AT&T. S commercial, service, in Pittsburgh, started, on June 30th. 1970. With 38, picture, phones at 8 companies, at a lease rate of 160. Dollars per month. 947. Dollars per month in 2012. Dollars, for the service, which provided, for 30 minutes of video calling, time per month with extra, minutes costing, 25, cents each color on AT&T picture. Phone was not employed with their early models, these. Picture, phone units package Plummer con cameras, and small court displays, within their housings, the.

Cameras, Were located, atop their screens to help users see eye to eye, later. Generation. Display, screens, were larger than in the original demonstration. Units approximately. 6 inches 15, centimeters, square in a rough cubical, cabinet. Topic. Picture-phone. Technology. The. Picture phones video bandwidth, was 1 megahertz with, a vertical scan, rate of 30 Hertz horizontal. Scan rate of 8 kilohertz and about, 250. Visible. Scan lines, the. Equipment, included, a speaker phone hands-free telephone, with, an added box to control picture, transmission. Each. Picture, phone line used 3 twisted, pairs of ordinary telephone cable, 2 pairs for video, and one for audio in signaling. Cable. Amplifiers, were spaced about a mile apart 1.6. Kilometers with, Bilt's and 6 band adjustable. Equalization. Filters, for. Distances, of more than a few miles the signal was digitized, at 2 megahertz and, 3 bits per sample dpcm. And transmitted. On a t2, carrier, the original, picture phone system, used contemporary. Crossbar, and multi frequency operation. Lines. And trunks were six wire one pair each way for video and one pair 2 way for audio, MF. Address signalling on the audio pair was supplemented, by a video supervisory. Signal, VSS, looping, around on the video quad to ensure continuity. More. Complex, protocols were, later adopted, for conferencing. To deploy picture, phone service, new wideband, crossbar, switches were designed, and installed into, the bell systems, five xbase switch offices, this being the most widespread of the relatively, modern kind. Hundreds. Of technicians, attended, schools to learn to operate the cable equalizer, test, set and other equipment, and to install picture, phones. Topic. Lack of picture phone success, at the time of its first launch AT&T. Foresaw, a hundred thousand picture phones in use across the Bell System by. 1975. However. By the end of July. 1974. Only, five picture, phones were being leased in Pittsburgh, and u.s. wide there were only a few hundred mostly. In Chicago. Unrelated. Difficulties, at New York telephone also. Slowed AT&T. S efforts, and few, customers signed up for the service in either city at.

Its Peak picture-phone service, had only about 500. Subscribers. With the service, fading, away through, the 1970s. AT&T. S initial, picture phone ma died model number one and then it's upgraded mod, two programs, were a continuation of, its many years of prior research, during, the 1920's. 1930's, late. 1940s. And 1950s. Both. Picture, phone programs, like their experimental, AT&T. Predecessors. Were researched, principally. At its Bell Labs formally, spanned some 15, years and consumed, more than 500. Million dollars, eventually. Meeting with commercial, failure. AT&T. Concluded. That its early picture, phone was a concept, looking, for a market, and discontinued. Its mod 2 service, in the late, 1970s. Topic. Later development. AT&T. Would later market, its videophone. 2500. To the general public from 1992. To, 1995. With prices, starting at. $1500. Approximately. Two thousand, six hundred and eighty dollars in current, dollars and later dropping, to one thousand, dollars one thousand, seven hundred and thirty dollars in current, dollars marketed. By its global video phone, systems, unit, the. Videophone. 2500. Was designed to provide low framerate compressed. Color video on ordinary, plain old telephone service pots, lines, circumventing. The significantly. Higher cost a DSL, telephone, service, lines used, by several other video conferencing. Manufacturers. It. Was limited, by analog, phone line connection, speeds of about nineteen, kilobits, per second, the video portion being. 11,200, bit/s and with a maximum, frame rate of 10 frames per second, but typically much slower as low as a third of a video frame per second, the. Video phone. 2500. Used proprietary, technology. Protocols, including, AT&T global, videophone. Standard, g vs, again. AT&T, met. With very little commercial, success, selling, only about 30 thousand, units mainly, outside the United, States despite a T and T's various, videophone, products, meeting with commercial, failure they were widely viewed as technical, successes, which expanded, the limits of the telecommunication. Sciences in several, areas, its. Video, telephony, programs, were critically, acclaimed for, their technical brilliance and, even the novel users they experimented. With the. Research, and development programs. Conducted, by Bell Labs were highly notable, for their beyond the state-of-the-art, results, produced in materials, science advanced. Telecommunications. Micro. Electronics, and information, technologies. AT&T. S published, research, additionally. Helped pave the way for other companies to later enter the field of video conferencing. The company's. Video phones also generated. Significant. Media coverage, in science, journals, the general news media, and in popular culture, the. Image of a futuristic. AT&T. Video phone being casually, used in the science fiction film. 2001. A Space Odyssey became. Iconic, of both the movie and arguably, the public's, general view of the future. Topic. Other early video phones. 1968. To 1999. Beginning. In the late 1960s. Several. Countries, worldwide sought, to compete with AT&T, s advanced, development, of its picture phone service, in the United, States, however. Such, projects, were research, and capital intensive, and fraught, with difficulties. In being deployed, commercially. This. Time period, also saw the research, development. And commercial, rollout, of what would become powerful, video compression, and decompression software. Codecs, which would eventually lead to low cost video telephony in the early 2000s. Topic. France france's, post office, telecommunications. Branch had earlier set up a commercial, video phone system, similar, to the german reich sposed public, video phone system, of the late 1930s.

In. 1972. The defense and electronics, manufacturer. Matra was one of three french companies, that sought to develop advanced, video phones. The early, 1970s. Spurred by the AT&T, picture. Phone in the United, States. Initial. Plans by mattre included, the deployment, of 25, units to Frances, centre national, de Tuesday's, telecommunications. CNET of France Telecom for their internal, use. CNET. Intended, to guide its initial, use towards, the business sector to be later followed, by personal. Home usage, its. Estimated, unit, cost in, 1971. Was the equivalent of. 325. Pounds, with a monthly, usage subscription. Charge of 3 pounds and 35, pence studies. Of applications. Of video telephony, were conducted, by C net in France in, 1972. With its first commercial, applications. For video phones appearing, in 1984. The. Delay was due to the problem of insufficient. Bandwidth, with 2 megabits, per second, being required, for transmitting, both video and audio signals. The. Problem, was solved worldwide, by the creation, of software for data encoding. And compression, via video coding, and decoding algorithms. Also known as codecs. Topic. Japan in Japan the luma phone was developed, and marketed by Mitsubishi. In, 1985. The. Project, was originally started. By the at retail, division, of the Atari video game company, in 1983. Under the direction of, Atari Steve, Bristow. Atari. Then sold, its division, to Mitsubishi, Electric, in 1984. The. Luma phone was marketed, by Mitsubishi, Electric, of America, in 1986. As the luma Liu 1000. Costing. $1500. Designed, with a small black-and-white, video display, approximately. 4 centimetres, 1.6. In in size and the video camera adjacent, to the display which could be blocked with a sliding, door for, privacy. Although. Promoted, as a video phone it operated, similar to Bell Labs early, experimental image. Transfer, phone of, 1956. Transmitting. Still images, every three to five seconds, over analog pots lines, it. Could also be hooked up to a printer, or connector, to a regular, TV or monitor for, improved, teleconferencing.

Mitsubishi. Also, marketed, its lower-cost, visit, l Lu 500. Image phone in 1988. Costing, about 400, dollars aimed at the consumer market. It, came with reduced, capabilities. But had with a larger, black-and-white display, other. Japanese. Electronic. Manufacturers. Marketed. Similar image transfer, phones during, the late 1980s. Including. Sony's PC T 15. $500. And two models from Panasonic, its wgr. To. 450, dollars and its KX TV 10, $500. Much later the Kyocera, corporation. An electronics. Manufacturer. Based in Kyoto conducted. A two-year, development campaign. From 1997. To 1999. That, resulted, in the release of the VP 210. Visual, phone the world's first mobile color, videophone that also doubled, as a camera, phone for still photos. The. Camera phone was the same size as similar, contemporary, mobile phones but sported, a large camera, lens and a 5 centimetres, 2 inch color TFT display. Capable, of displaying. 65,000. Colors and was able to process two video frames per second, the. 155. Gram five point five ounces camera. Could also take twenty photos and convey them by email with the camera, phone retailing, at the time for 40 thousand yen about three, hundred and twenty-five dollars in, 1999. The VP 210. Was released in May 1999. And, used its single front-facing. 110,000. Pixel, camera to send two images, per second, through Japan's PHS. Mobile, phone network, system, although. Its frame rate was crude and its memory is considered, tiny in the present day the phone was viewed as revolutionary. At the time of its release the, Kyocera project. Was initiated, at their yokohama research, and development, center by Kazumi, suburi, one of their section, managers, his. Explanation. For the project, was around that time cellular. Handsets with, enabled, voice and SMS communication. Capabilities. Were considered, to be just one among many personal, communication. Tools, one. Day a simple, idea hit us what if we were able to enjoy talking with the intended, person, watching, his perfo splay. We were certain, that such a device, would make cell phone communications. Much more convenient, and enjoyable. Suburi also, stated, that their R&D, section, had nourished the idea for several years before they received project, approval, from their top management, which had encouraged, such forward-thinking, research. Because, they also believed, that such a product, would improve kyocera's, brand image, their research, showed that a cell phone with a camera and color display, provided, a completely, new value for users it could be used as a phone a camera and a photo album technical. Challenges, handled, by about a dozen engineers, at Kyocera, over the two-year development period. Included, the camera modules, placement, within the phone at a time when electronic, components. Had not been fully reduced, in size as well as increasing, its data transmission. Rate after. Its release the mobile video, camera, phone was commercially, successful spawning.

Several, Other competitors. Such as the DDI pocket, and one from Vodafone KK. Topic. Sweden in sweden electronics. Maker ericsson, began developing, a videophone in the mid 1960s. Intending. To market it to government, institutions. Businesses. And industry, but not to consumers, due to AT&T s lack of success in that market, segment. Tests. Were conducted in, Stockholm, including, trial communications. In banking, ultimately. Ericsson, chose not to proceed with further production. Topic. United, Kingdom in 1970. The British general post, office had 16, demonstration. Models of its view phone built meant to be the equivalent or AT&T x' picture, phone their. Initial, attempt, at a first generation commercial. Videophone later led to the British Telecom, relate 2000, which was released for sale in, 1993. Costing, between 400. Pounds, to 500, pounds each, the. Relate, 2005. 274. Millimeters, 2.9. In flip-up color LCD display. Screen operating, at a nominal rate, of 8 video frames, per second, which could be depressed, to 3 to 4 frames, per second, if the PSTN. Bandwidth, was limited, in. The era prior to low-cost high speed broadband, service, its video quality was, found to be generally, poor by the public, with images, shifting, jerkily, between frames due to British phone lines that generally, provided, less than 3.4, kilohertz of bandwidth. British. Telecom, had initially expected. The device manufactured. By Marconi, electronics. To sell at a rate of 10,000. Per years but its actual sales were minimal, its. Second-generation. Videophone. Thus also proved, to be commercially, unsuccessful, similar. To AT&T x' videophone. 2500. Of the same time period. Topic. Videophone. Improvements. Post-2000. Significant. Improvements. In video call quality of service, for the deaf occurred, in the United States in 2003. When Sorenson, Media Inc formally Sorenson, vision a video compression, software coding, company, developed. Its VP 100. Model standalone, video phones specifically. For the deaf community, it. Was designed to output, its video to the users television, in order to lower the cost of acquisition and, to offer remote control, and a powerful video compression. Codec, for unequaled video quality and ease of use with a video relay, service, VRS. Favorable. Reviews quickly led to its popular, usage, at educational. Facilities, for the Deaf and from there to the greater deaf community, coupled, with similar, high quality, video phones introduced, by other electronics. Manufacturers. The availability, of high speed internet and sponsored, video relay, services, authorized, by the US, Federal, Communications, Commission. In 2002. VRS. Services, for the deaf underwent, rapid, growth in that country. Topic. See, also. History. Of mobile phones. History. Of radio. History. Of telecommunication. History. Of the telephone. History. Of television. List. Of video, telecommunication. Services, and product brands. Telepresence. Timeline. Of communication. Technology. Timeline. Of the telephone. Video. Conferencing. Video. Phone. Webcam. Equals. Equals, notes.

2019-01-13 12:01

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