Telephone exchange in the context of "Relay"

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⭐ Core Definition: Telephone exchange

A telephone exchange, telephone switch, or central office is a central component of a telecommunications system in the public switched telephone network (PSTN) or in large enterprises. It facilitates the establishment of communication circuits, enabling telephone calls between subscribers. The term "central office" can also refer to a central location for fiber optic equipment for a fiber internet provider.

In historical perspective, telecommunication terminology has evolved with time. The term telephone exchange is often used synonymously with central office, a Bell System term. A central office is defined as the telephone switch controlling connections for one or more central office prefixes. However, it also often denotes the building used to house the inside plant equipment for multiple telephone exchange areas. In North America, the term wire center may be used to denote a central office location, indicating a facility that provides a telephone with a dial tone. Telecommunication carriers also define rate centers for business and billing purposes, which in large cities, might encompass clusters of central offices to specify geographic locations for distance measurement calculations.

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👉 Telephone exchange in the context of Relay

A relay is an electrically operated switch. It has a set of input terminals for one or more control signals, and a set of operating contact terminals. The switch may have any number of contacts in multiple contact forms, such as make contacts, break contacts, or combinations thereof.

Relays are used to control a circuit by an independent low-power signal and to control several circuits by one signal. They were first used in long-distance telegraph circuits as signal repeaters that transmit a refreshed copy of the incoming signal onto another circuit. Relays were used extensively in telephone exchanges and early computers to perform logical operations.

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Telephone exchange in the context of Telephone number

A telephone number is the address of a telecommunication endpoint, such as a telephone, in a telephone network, such as the public switched telephone network (PSTN). A telephone number typically consists of a sequence of digits, but historically letters were also used in connection with telephone exchange names.

Telephone numbers facilitate the switching and routing of calls using a system of destination code routing. Telephone numbers are entered or dialed by a calling party on the originating telephone set, which transmits the sequence of digits in the process of signaling to a telephone exchange. The exchange completes the call either to another locally connected subscriber or via the PSTN to the called party. Telephone numbers are assigned within the framework of a national or regional telephone numbering plan to subscribers by telephone service operators, which may be commercial entities, state-controlled administrations, or other telecommunication industry associations.

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Telephone exchange in the context of Sender (telephony)

A sender is a type of circuit and system module in 20th-century electromechanical telephone exchanges. It registered the telephone numbers dialed by the subscriber, and transmitted that information to another part of the exchange or another exchange for the purpose of completing a telephone call. Some American exchange designs, for example, of the No. 1 Crossbar switch used originating senders and terminating senders. The corresponding device in the British director telephone system was called a "director" and, in other contexts, "register".

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Telephone exchange in the context of Rotary dial

A rotary dial is a component of a telephone or a telephone switchboard that implements a signaling technology in telecommunications known as pulse dialing. It is used when initiating a telephone call to transmit the destination telephone number to a telephone exchange as a succession of individual digits.

On the rotary dial, the digits are arranged in a circular layout, with one finger hole in the finger wheel for each digit. For dialing a digit, the wheel is rotated against spring tension with one finger positioned in the corresponding hole, pulling the wheel with the finger to a stop position given by a mechanical barrier, the finger stop. When released at the finger stop, the wheel returns to its home position driven by the spring at a speed regulated by a governor device. During this return rotation, an electrical switch interrupts the direct current (DC) of the telephone line (local loop) the specific number of times associated with each digit and thereby generates electrical pulses which the telephone exchange decodes into each dialed digit. Thus, each of the ten digits is encoded in sequences to correspond to the number of pulses; thus, the method is sometimes called decadic dialing. Pulse count dialing is a digital addressing system which uses decimal pulse count modulation. The typical average baud rate is 10 bits per second, though the system will usually accept from about 9 through 13 pulses per second, a requirement due to variations in the rotary dial mechanism governor speed.

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Telephone exchange in the context of Telephone exchange names

A telephone exchange name or central office name was a distinguishing and memorable name assigned to a central office. It identified the switching system to which a telephone was connected, and facilitated the connection of telephone calls between switching systems in different localities.

While small towns and rural areas might each be served by a single exchange, large cities were served by multiple switching systems, either distributed in the community constituting multiple exchange areas, or sometimes hosted in the same building to serve a densely populated area. Central offices were usually identified by names that were locally significant. The leading letters of a central office name were used as the leading components of the telephone number representation, so that each telephone number in the area was unique. These letters were mapped to the digits of the dial, which was indicated visibly on the dial's numbering plate.

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Telephone exchange in the context of C++

C++ is a high-level, general-purpose programming language created by Danish computer scientist Bjarne Stroustrup. First released in 1985 as an extension of the C programming language, adding object-oriented (OOP) features, it has since expanded significantly over time adding more OOP and other features; as of 1997/C++98 standardization, C++ has added functional features, in addition to facilities for low-level memory manipulation for systems like microcomputers or to make operating systems like Linux or Windows, and even later came features like generic programming (through the use of templates). C++ is usually implemented as a compiled language, and many vendors provide C++ compilers, including the Free Software Foundation, LLVM, Microsoft, Intel, Embarcadero, Oracle, and IBM.

C++ was designed with systems programming and embedded, resource-constrained software and large systems in mind, with performance, efficiency, and flexibility of use as its design highlights. C++ has also been found useful in many other contexts, with key strengths being software infrastructure and resource-constrained applications, including desktop applications, video games, servers (e.g., e-commerce, web search, or databases), and performance-critical applications (e.g., telephone switches or space probes).

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Telephone exchange in the context of Bridgeport, Connecticut

Bridgeport is the most populous city in the U.S. state of Connecticut and the fifth-most populous city in New England, with a population of 148,654 in 2020. Located in eastern Fairfield County at the mouth of the Pequonnock River on Long Island Sound, it is a port city 60 miles (97 km) from Manhattan and 40 miles (64 km) from The Bronx. It borders the towns of Trumbull to the north, Fairfield to the west, and Stratford to the east. Bridgeport and other towns in Fairfield County make up the Greater Bridgeport Planning Region, as well as the Bridgeport–Stamford–Norwalk–Danbury metropolitan statistical area, the second largest metropolitan area in Connecticut. The Bridgeport–Stamford–Norwalk–Danbury metropolis forms part of the New York metropolitan area.

Inhabited by the Paugussett Native American tribe until English settlement in the 1600s, Bridgeport was incorporated in 1821 as a town, and as a city in 1836. Showman P. T. Barnum was a resident of the city and served as the town's mayor (1871). Barnum built four houses in Bridgeport and housed his circus in town during winter. The city in the early 20th century saw an economic and population boom, becoming by all measures Connecticut's chief manufacturing city by 1905. Bridgeport was the site of the world's first mutual telephone exchange (1877), the first dental hygiene school (1949), and the first bank telephone bill service in the US (1981). Inventor Harvey Hubbell II invented the electric plug outlet in Bridgeport in 1912. The Frisbie Pie Company was founded and operated in Bridgeport. The world's first Subway restaurant opened in the city's North End in 1965. After World War II, industrial restructuring and suburbanization caused the loss of many large companies and affluent residents, leaving Bridgeport struggling with issues of poverty and violent crime.

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Telephone exchange in the context of 1XB switch

The Number One Crossbar Switching System (1XB), was the primary technology for urban telephone exchanges served by the Bell System in the mid-20th century. Its switch fabric used the electromechanical crossbar switch to implement the topology of the panel switching system of the 1920s. The first No. 1 Crossbar was installed in the PResident-2 central office at Troy Avenue in Brooklyn, New York which became operational in February 1938.

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Telephone exchange in the context of Trunking

In telecommunications, trunking is a technology for providing network access to multiple clients simultaneously by sharing a set of circuits, carriers, channels, or frequencies, instead of providing individual circuits or channels for each client. This is reminiscent to the structure of a tree with one trunk and many branches. Trunking in telecommunication originated in telegraphy, and later in telephone systems where a trunk line is a communications channel between telephone exchanges.

Other applications include the trunked radio systems commonly used by police agencies.

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