Paradyne COMSPHERE 3920PLUS Series, Техническое справочное руководство

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COMSPHERE 392xPlus Modems
Glossary-4 October 1998 3920-A2-GH30-40
Data mode A state where any entries made from the DTE are considered data and are transmitted
and received between modems. Modems remain in Data mode until the connection is
broken or until they are forced into online Command mode using the escape sequence.
DB-25 connector A 25-pin connector that is used to connect a cable which enables communication
between two devices.
dBm A decibel referenced to one milliwatt. This unit measures relative signal power.
DCE Data Communications Equipment (or Data Circuit Terminating Equipment). Generally
refers to to a modem or other data transmission devices that provides the functions
required to establish, maintain, and end a connection. This equipment also provides the
signal conversion required for communication between the DTE and the telephone line.
DCP Diagnostic Control Panel. The face of the modem that continuously provides status
information about the modem’s operation and allows an operator to manage its operation.
This is a generic term used for both the standalone and carrier-mounted models. See
SDCP.
data compression The elimination of empty fields, redundancies, and gaps to reduce storage capacity needs
and the amount of data to be transmitted. Anything that is compressed is restored after
the data is received.
demodulation The process of recovering data from a modulated carrier wave.
DevHS Device Health and Status. A detailed account of device alarms.
Diagnostic Channel (DC) The diagnostic interface between two network devices, used to extend the NMS
diagnostics to downstream devices.
dial command modifiers A modifier used in the dial string that instructs the modem how to process a dialed
telephone number.
dial line A communications circuit that is established by a switched circuit connection in the dial
network.
dial network See PSTN.
Dial Standby A function available when the modem is operating in Dial Backup mode, allowing the
modem to switch back to lease-line operation while still maintaining the dial-line
connection.
dial string A series of characters that consists of numbers and modifiers used to dial a telephone
number.
digital bridging Provides the capability of dial backup in a multipoint configuration by bridging the
signal on the digital side of the front end panel.
digital signal processor
(DSP) A microprocessor designed to perform and execute mathematically intense calculations
and algorithms at high speeds, in real time, for various DSP applications. It is mostly
used in DSP applications involved in the sampling of a signal, such as digital filtering,
speech vocoding, image processing, fast Fourier transforms, digital audio, and data
transmission.