1.
Retronym
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A retronym is a neologism for a word created to differentiate between two words, where previously no clarification was required. Advances in technology are responsible for the coinage of retronyms. For example, the acoustic guitar was coined at the advent of electric guitars. Since the end of the 19th century, most bicycles have been expected to have two equal sized wheels, and the type has been renamed penny-farthing or high-wheeler bicycle. Similarly, the term cisgender was coined to describe persons who identify with the gender they were assigned at birth, the term retronym was coined by Frank Mankiewicz in 1980 and popularized by William Safire in The New York Times Magazine. In 2000 The American Heritage Dictionary became the first major dictionary to include the word retronym, back-formation Backronym Contrastive focus reduplication -onym Protologism
2.
Telephone
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A telephone, or phone, is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be heard directly. In 1876, Scottish emigrant Alexander Graham Bell was the first to be granted a United States patent for a device that produced clearly intelligible replication of the human voice and this instrument was further developed by many others. The telephone was the first device in history that people to talk directly with each other across large distances. Telephones rapidly became indispensable to businesses, government, and households, the essential elements of a telephone are a microphone to speak into and an earphone which reproduces the voice in a distant location. Until approximately the 1970s most telephones used a dial, which was superseded by the modern DTMF push-button dial. The receiver and transmitter are usually built into a handset which is held up to the ear, the dial may be located either on the handset, or on a base unit to which the handset is connected. The transmitter converts the sound waves to electrical signals which are sent through the network to the receiving phone. The receiving telephone converts the signals into audible sound in the receiver, telephones permit duplex communication, meaning they allow the people on both ends to talk simultaneously. The first telephones were connected to each other from one customers office or residence to another customers location. Being impractical beyond just a few customers, these systems were replaced by manually operated centrally located switchboards. For greater mobility, various systems were developed for transmission between mobile stations on ships and automobiles in the middle 20th century. Hand-held mobile phone]s was introduced for personal service starting in 1973, by the late 1970s several mobile telephone networks operated around the world. In 1983, the Advanced Mobile Phone System was launched, offering a standardized technology providing portability for users far beyond the residence or office. These analog cellular system evolved into digital networks with better security, greater capacity, better regional coverage, the public switched telephone network, with its hierarchical system of many switching centers, interconnects telephones around the world for communication with each other. With the standardized international numbering system, E.164, each line has an identifying telephone number. Although originally designed for voice communications, convergence has enabled most modern cell phones to have many additional capabilities. Since 1999, the trend for mobile phones is smartphones that integrate all mobile communication, a traditional landline telephone system, also known as plain old telephone service, commonly carries both control and audio signals on the same twisted pair of insulated wires, the telephone line. The control and signaling equipment consists of three components, the ringer, the hookswitch, and a dial, the ringer, or beeper, light or other device, alerts the user to incoming calls
3.
Integrated Services Digital Network
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It was first defined in 1988 in the CCITT red book. Prior to ISDN, the system was viewed as a way to transport voice. The key feature of ISDN is that it integrates speech and data on the same lines, the ISDN standards define several kinds of access interfaces, such as Basic Rate Interface, Primary Rate Interface, Narrowband ISDN, and Broadband ISDN. It offers circuit-switched connections, and packet-switched connections, in increments of 64 kilobit/s, in some countries, ISDN found major market application for Internet access, in which ISDN typically provides a maximum of 128 kbit/s bandwidth in both upstream and downstream directions. Channel bonding can achieve a data rate, typically the ISDN B-channels of three or four BRIs are bonded. ISDN is employed as the network, data-link and physical layers in the context of the OSI model, or could be considered a suite of digital services existing on layers 1,2, and 3 of the OSI model. In a videoconference, ISDN provides simultaneous voice, video, Integrated services refers to ISDNs ability to deliver at minimum two simultaneous connections, in any combination of data, voice, video, and fax, over a single line. Multiple devices can be attached to the line, and used as needed and that means an ISDN line can take care of most peoples complete communications needs at a much higher transmission rate, without forcing the purchase of multiple analog phone lines. It also refers to integrated switching and transmission in that telephone switching, the entry level interface to ISDN is the Basic Rate Interface, a 128 kbit/s service delivered over a pair of standard telephone copper wires. The 144 kbit/s payload rate is broken down into two 64 kbit/s bearer channels and one 16 kbit/s signaling channel and this is sometimes referred to as 2B+D. The T interface is an interface between a computing device and a terminal adapter, which is the digital equivalent of a modem. The S interface is a bus that ISDN consumer devices plug into. The R interface defines the point between a device and a terminal adapter which provides translation to and from such a device. BRI-ISDN is very popular in Europe but is less common in North America. It is also common in Japan — where it is known as INS64, the other ISDN access available is the Primary Rate Interface, which is carried over an E1 in most parts of the world. An E1 is 30 B channels of 64 kbit/s, one D channel of 64 kbit/s and this is often referred to as 30B+2D. In North America PRI service is delivered on one or more T1 carriers of 1544 kbit/s, a PRI has 23 B channels and 1 D channel for signalling. Inter-changeably but incorrectly, a PRI is referred to as T1 because it uses the T1 carrier format, a true T1 uses 24 channels of 64 kbit/s of in-band signaling
4.
Mobile phone
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A mobile phone is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the systems of a mobile phone operator. Most modern mobile telephone services use a network architecture, and, therefore. Mobile phones which offer these and more general computing capabilities are referred to as smartphones, the first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing c.4.4 lbs. In 1983, the DynaTAC 8000x was the first commercially available mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to seven billion, penetrating 100% of the global population. In first quarter of 2016, the top smartphone manufacturers were Samsung, Apple, a handheld mobile radio telephone service was envisioned in the early stages of radio engineering. In 1917, Finnish inventor Eric Tigerstedt filed a patent for a pocket-size folding telephone with a thin carbon microphone. Early predecessors of cellular phones included analog radio communications from ships, the race to create truly portable telephone devices began after World War II, with developments taking place in many countries. These 0G systems were not cellular, supported few simultaneous calls, the first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing c.4.4 lbs. The first commercial automated cellular network was launched in Japan by Nippon Telegraph and this was followed in 1981 by the simultaneous launch of the Nordic Mobile Telephone system in Denmark, Finland, Norway, and Sweden. Several other countries followed in the early to mid-1980s. These first-generation systems could support far more simultaneous calls but still used analog cellular technology, in 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. In 1991, the digital cellular technology was launched in Finland by Radiolinja on the GSM standard. This sparked competition in the sector as the new operators challenged the incumbent 1G network operators, ten years later, in 2001, the third generation was launched in Japan by NTT DoCoMo on the WCDMA standard. This was followed by 3. 5G, 3G+ or turbo 3G enhancements based on the high-speed packet access family, allowing UMTS networks to have data transfer speeds. By 2009, it had become clear that, at point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications. Consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies
5.
Dual-tone multi-frequency signaling
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DTMF was first developed in the Bell System in the United States, and became known under the trademark Touch-Tone for use in push-button telephones supplied to telephone customers, starting in 1963. DTMF is standardized by ITU-T Recommendation Q.23 and it is also known in the UK as MF4. The Touch-Tone system using a telephone keypad gradually replaced the use of dial and has become the industry standard for landline. Other multi-frequency systems are used for internal signaling within the telephone network, prior to the development of DTMF, telephone numbers were dialed by users with a loop-disconnect signaling, more commonly known as pulse dialing in the U. S. The exchange equipment responds to the dial pulses either directly by operating relays, the physical distance for which this type of dialing was possible was restricted by electrical distortions and was only possible on direct metallic links between end points of a line. Placing calls over longer distances required either operator assistance or provision of special subscriber trunk dialing equipment, operators used an earlier type of multi-frequency signaling. Multi-frequency signaling is a group of signaling methods that use a mixture of two pure tone sounds, various MF signaling protocols were devised by the Bell System and CCITT. This semi-automated signaling and switching proved successful in both speed and cost effectiveness, the DTMF system uses a set of eight audio frequencies transmitted in pairs to represent 16 signals, represented by the ten digits, the letters A to D, and the symbols # and *. AT&T described the product as a method for pushbutton signaling from customer stations using the transmission path. DTMF was known throughout the Bell System by the trademark Touch-Tone, the term was first used by AT&T in commerce on July 5,1960 and was introduced to the public on November 18,1963, when the first push-button telephone was made available to the public. It was a trademark by AT&T from September 4,1962 to March 13,1984. It is standardized by ITU-T Recommendation Q.23, in the UK, it is also known as MF4. Other vendors of compatible telephone equipment called the Touch-Tone feature tone dialing or DTMF, previously, terrestrial television stations used DTMF tones to control remote transmitters. The engineers had envisioned telephones being used to access computers, and they consulted with companies to determine the requirements. This led to the addition of the sign and asterisk or star keys as well as a group of keys for menu selection. Public payphones that accept credit cards use these codes to send the information from the magnetic strip. The AUTOVON telephone system of the United States Armed Forces used these signals to assert certain privilege, precedence is still a feature of military telephone networks, but using number combinations. For example, entering 93 before a number is a priority call, present-day uses of the A, B, C and D signals on telephone networks are few, and are exclusive to network control
6.
Telephone exchange
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A telephone exchange is a telecommunications system used in the public switched telephone network or in large enterprises. In historical perspective, telecommunication terms have been used with different semantics over time, the term telephone exchange is often used synonymously with central office, a Bell System term. Often, an office is defined as a building used to house the inside plant equipment of potentially several telephone exchanges. Such an area has also referred to as the exchange. Central office locations may also be identified in North America as wire centers, All central offices within a larger region, typically aggregated by state, were assigned a common numbering plan area code. For corporate or enterprise use, a telephone exchange is often referred to as a private branch exchange. Smaller installations might deploy a PBX or key telephone system in the office of a receptionist and this made it possible for subscribers to call each other at homes, businesses, or public spaces. These made telephony an available and comfortable communication tool for everyday use, one of the first to propose a telephone exchange was Hungarian Tivadar Puskás in 1877 while he was working for Thomas Edison. The first experimental telephone exchange was based on the ideas of Puskás, the worlds first commercial telephone exchange opened on November 12,1877 in Friedrichsberg close to Berlin. George W. Coy designed and built the first commercial US telephone exchange opened in New Haven. The switchboard was built from carriage bolts, handles from teapot lids and bustle wire, Charles Glidden is also credited with establishing an exchange in Lowell, MA. with 50 subscribers in 1878. In Europe other early telephone exchanges were based in London and Manchester, Belgium had its first International Bell exchange a year later. In 1887 Puskás introduced the multiplex switchboard, later exchanges consisted of one to several hundred plug boards staffed by switchboard operators. Each operator sat in front of a panel containing banks of ¼-inch tip-ring-sleeve jacks. In front of the jack panel lay a horizontal panel containing two rows of patch cords, each connected to a cord circuit. When a calling party lifted the receiver, the loop current lit a signal lamp near the jack. The operator responded by inserting the rear cord into the jack and switched her headset into the circuit to ask, Number. For a local call, the operator inserted the front cord of the pair into the partys local jack
7.
Fiber-optic communication
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Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber. The light forms a carrier wave that is modulated to carry information. Fiber is preferred over electrical cabling when high bandwidth, long distance, optical fiber is used by many telecommunications companies to transmit telephone signals, Internet communication, and cable television signals. Researchers at Bell Labs have reached speeds of over 100 petabit×kilometer per second using fiber-optic communication. First developed in the 1970s, fiber-optics have revolutionized the industry and have played a major role in the advent of the Information Age. Because of its advantages over electrical transmission, optical fibers have largely replaced copper wire communications in core networks in the developed world, due to much lower attenuation and interference, optical fiber has large advantages over existing copper wire in long-distance and high-demand applications. However, infrastructure development within cities was difficult and time-consuming. Since 2000, the prices for fiber-optic communications have dropped considerably, the price for rolling out fiber to the home has currently become more cost-effective than that of rolling out a copper based network. Prices have dropped to $850 per subscriber in the US and lower in countries like The Netherlands, since 1990, when optical-amplification systems became commercially available, the telecommunications industry has laid a vast network of intercity and transoceanic fiber communication lines. Bell considered it his most important invention, the device allowed for the transmission of sound on a beam of light. On June 3,1880, Bell conducted the worlds first wireless transmission between two buildings, some 213 meters apart. Due to its use of a transmission medium, the Photophone would not prove practical until advances in laser. The Photophones first practical use came in military communication systems many decades later, in 1954 Harold Hopkins and Narinder Singh Kapany showed that rolled fiber glass allowed light to be transmitted. Initially it was considered that the light can traverse in only straight medium, after a period of research starting from 1975, the first commercial fiber-optic communications system was developed, which operated at a wavelength around 0.8 µm and used GaAs semiconductor lasers. This first-generation system operated at a bit rate of 45 Mbit/s with repeater spacing of up to 10 km, soon on 22 April 1977, General Telephone and Electronics sent the first live telephone traffic through fiber optics at a 6 Mbit/s throughput in Long Beach, California. The second generation of fiber-optic communication was developed for use in the early 1980s, operated at 1.3 µm. In 1984, they had developed a fiber optic cable that would help further their progress toward making fiber optic cables that would circle the globe. Canadian service provider SaskTel had completed construction of what was then the world’s longest commercial fiberoptic network, by 1987, these systems were operating at bit rates of up to 1.7 Gb/s with repeater spacing up to 50 km
