telecommunications Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...

, the term concentrator has the following meanings: * In

data transmission Data communication, including data transmission and data reception, is the transfer of data, signal transmission, transmitted and received over a Point-to-point (telecommunications), point-to-point or point-to-multipoint communication chann ...

, a

functional unit In computer engineering, an execution unit (E-unit or EU) is a part of a processing unit that performs the operations and calculations forwarded from the instruction unit. It may have its own internal control sequence unit (not to be confused wi ...

that permits a common

path A path is a route for physical travel – see Trail. Path or PATH may also refer to: Physical paths of different types * Bicycle path * Bridle path, used by people on horseback * Course (navigation), the intended path of a vehicle * Desir ...

to handle more data sources than there are channels currently available within the path. A concentrator usually provides communication capability between many low-speed, usually asynchronous channels and one or more high-speed, usually

synchronous Synchronization is the coordination of events to operate a system in unison. For example, the conductor of an orchestra keeps the orchestra synchronized or ''in time''. Systems that operate with all parts in synchrony are said to be synchrono ...

channels. Usually different speeds, codes, and protocols can be accommodated on the low-speed side. The low-speed channels usually operate in contention and require buffering. * A device that connects a number of links with only one destination, the main function of this device is to make a kind of load balancing between two or more servers connected together, data distribution is done according to the server processing rate. * A

patch panel A patch panel is a device or unit featuring a number of jacks, usually of the same or similar type, for the use of connecting and routing circuits for monitoring, interconnecting, and testing circuits in a convenient, flexible manner. Patch ...

or other component in the

cable plant In telecommunications, structured cabling is building or campus cabling infrastructure that consists of a number of standardized smaller elements (hence structured) called subsystems. Structured cabling components include twisted pair and opti ...

where cable runs converge. *

ISP An Internet service provider (ISP) is an organization that provides a myriad of services related to accessing, using, managing, or participating in the Internet. ISPs can be organized in various forms, such as commercial, community-owned, non ...

used concentrators to enable

modem The Democratic Movement (, ; MoDem ) is a centre to centre-right political party in France, whose main ideological trends are liberalism and Christian democracy, and that is characterised by a strong pro-Europeanist stance. MoDem was establis ...

dialing; this kind of concentrator is sometimes called a modem concentrator or a remote access concentrator. The term "access concentrator" is also used to describe similar

provider edge A provider edge router (PE router) is a router between one network service provider's area and areas administered by other network providers. A network provider is usually an Internet service provider as well (or only that). The term ''PE rout ...

equipment used in computer networks that doesn't rely on modems anymore, e.g.

FTTH Fiber to the ''x'' (FTTX; also spelled "fibre") or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications. As fiber opt ...

.See how the term is used in RFC 2516 (

PPPoE The Point-to-Point Protocol over Ethernet (PPPoE) is a network protocol for Encapsulation (networking), encapsulating Point-to-Point Protocol (PPP) frames inside Ethernet frames. It appeared in 1999, in the context of the boom of DSL as the solu ...

) for example

Theory

In the evolution of modern telecommunications systems there was a requirement to connect large numbers of low-speed access devices with large telephone company 'central office' switches over common paths. During the first generations of digital networks, analog signals were digitized on line cards attached to the

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 ...

switches. In an effort to reduce

local loop In telephony, the local loop (also referred to as the local tail, subscriber line, or in the aggregate as the last mile) is the physical link or circuit that connects from the demarcation point of the customer premises to the edge of the co ...

costs, it was decided to push this conversion closer to the customer premises by deploying small conversion devices in customer neighborhoods. These devices would combine multiple digital signals on a single link to a larger telephone switch, which would provide service to the customer. These devices were initially called

remote concentrator In modern telephony a remote concentrator, remote concentrator unit (RCU), or remote line concentrator (RLC) is a concentrator at the lowest level in the telephone switch hierarchy. Subscribers' analogue telephone/PSTN lines are terminated on con ...

s or simply remotes. In fibre-optic distribution systems which offer triple-play services (voice, television, internet) the digitization has arrived at the customer premises and signals are digitized at the source and combined using customer edge routers. This traffic enters the distribution network at an Optical Network Termination and is carried to the central office using

Wavelength division multiplexing In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (i.e., colors) of laser light. This techni ...

and

Passive optical network A passive optical network (PON) is a fiber-optic telecommunications network that uses only ''unpowered'' devices to carry signals, as opposed to electronic equipment. In practice, PONs are typically used for the '' last mile'' between Internet ...

ing.

References

Telecommunications equipment {{Telecomm-stub ru:Концентраторы

Theory

See also

References