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Data Communications Equipment
Equipment that is used to access a communications network. The DCE provides all the
functions required to establish, maintain and terminate a connection, and provides the signal
conversion required for communications between the Data Terminal Equipment (DTE) and the
telephone network. With RS-232 connections, the modem is generally the DCE device while the
computer or terminal connected to a modem is generally the DTE device. See also Data Terminal
Equipment.
Data Compression
An encoding technique which provides for the transmission of fewer data bits without the loss
of information. The receiving end expands the data received to its original form.
Data Set
See Data Communictions Equipment and Modem.
Data Set Ready (DSR)
An RS-232 control signal used to indicate the readiness of the DCE (Usually a modem) to accept
data from the DTE (usually a terminal or computer).
Data Terminal Equipment (DTE)
The equipment which provides the data source and/or receiving end of a data transmission link.
The DTE may be a CRT or teletype terminal, a personal computer, a printer, a front-end
processor to a large mainframe computer or any other device which can transmit or receive data.
With RS-232 connections the designation of DTE or DCE determines which device is
responsible for generating certain control signals. See also Data Communications Equipment.
Data Terminal Ready (DTR)
An RS-232 control signal used to indicate the readiness of the DTE for data transmission.
DCD
An acronym for Data Carrier Detect. See also Carrier Detect.
DCE
An acronym of Data Communications Equipment. See Data Communications Equipment.
Decibel (dB)
Unit of measure indicating the logarithmic ratio of output signal power to input signal power.
Dedicated Line
A communications line which is not dialed. Also known as a leased or private line.