A data circuit-terminating equipment (DCE) is a device that sits between the

data terminal equipment Data terminal equipment (DTE) is an end instrument that converts user information into signals or reconverts received signals. It is also called data processing terminal equipment or tail circuit. A DTE device communicates with the data cir ...

(DTE) and a data transmission circuit. It is also called data communication(s) equipment and data carrier equipment. Usually, the DTE device is the terminal (or

computer A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...

), and the DCE is a

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 ...

. In a ''data station'', the DCE performs functions such as

signal A signal is both the process and the result of transmission of data over some media accomplished by embedding some variation. Signals are important in multiple subject fields including signal processing, information theory and biology. In ...

conversion, coding, and line clocking and may be a part of the DTE or intermediate equipment. Interfacing equipment may be required to couple the DTE into a transmission circuit or channel and from a transmission circuit or channel into the DTE.

Usage

Although the terms are most commonly used with RS-232, several data communication standards define different types of interfaces between a DCE and a DTE. The DCE is a device that communicates with a DTE device in these standards. Standards that use this nomenclature include: * Federal Standard 1037C, MIL-STD-188 * RS-232 * Certain

ITU-T The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) is one of the three Sectors (branches) of the International Telecommunication Union (ITU). It is responsible for coordinating Standardization, standards fo ...

standards in the V series (notably V.24 and V.35) * Certain

standards in the X series (notably X.21 and

X.25 X.25 is an ITU-T standard protocol suite for Packet switched network, packet-switched data communication in wide area network, wide area networks (WAN). It was originally defined by the CCITT, International Telegraph and Telephone Consultative Co ...

) A general rule is that DCE devices provide the clock signal (internal clocking) and the DTE device synchronizes on the provided clock (external clocking). D-sub connectors follow another rule for pin assignment. DTE devices usually transmit on pin connector number 2 and receive on pin connector number 3. DCE devices are just the opposite: pin connector number 2 receives and pin connector number 3 transmits the signals. When two devices, that are both DTE or both DCE, must be connected together without a modem or a similar media translator between them, a crossover cable must be used, e.g. a null modem for RS-232 or an

Ethernet Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...

crossover cable.

References

External links

Data Terminating Equipment or Data Circuit-Terminating Equipment speeds
IBM {{Authority control Data transmission Telecommunications equipment

Usage

See also

References

External links