Paradyne COMSPHERE 3920PLUS Series, Technical Reference Manual

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Glossary
Glossary-3 3920-A2-GH30-40 October 1998
character echo A way to check the accuracy of data transmission by sending to the monitor (displaying)
all the characters being transmitted.
circuit pack lock A screw lock tab installed over a circuit card’s latch release tab to prevent the unit from
being removed without a tool. It is used on SDUs, modems, and filler panels.
Command mode The modem accepts AT commands instead of transmitting or receiving data on the DTE.
See Data mode.
compandor A combination of a compressor at one point in a communication path for reducing the
volume range of signals, followed by an expandor at another point for restoring the
original volume range. Usually its purpose is to improve the ratio of the signal to the
interference in the path between the compressor and expandor.
configuration area One of five areas within the Configure branch containing modem settings. Configuration
areas include Active (Operating), Active (Saved), Customer 1, Customer 2, and Factory.
configuration option Modem software that sets specific operating parameters for the modem. Sometimes
referred to as straps.
connector An outlet on equipment and cables that provides a connection.
constant carrier mode The modem transmits a carrier signal constantly, regardless of RTS.
Control Channel (CC) The diagnostic interface between a network management system and a network device.
control modem A control modem polls downstream tributary modems across the analog channel.
controlled carrier mode The modem’s transmitter turns on and off in response to RTS. This mode is used by
multipoint tributary modems.
CTS Clear to Send. A signal indicating that the device is ready for the DTE to transmit data.
Usually occurs in response to Request to Send (RTS).
Customer 1 A user-defined configuration area containing customized configuration options for a
specific application.
Customer 2 A user-defined configuration area containing customized configuration options for a
specific application.
DAA Data Access Arrangement. Hardware that acts as a protective interface between the
telephone circuit and the modem. It performs such functions as ring detection, DC
isolation, and surge protection to protect the circuit from being disturbed by a modem
malfunction. The 392xPlus modems contain three dip switches that allow the DAA
hardware to be configured for use in different countries.
data bank An area within the modem used to store the modem’s firmware. There are two data
banks in the 392xPlus modem.
data carrier A continuous frequency signal that can be modulated by another signal that contains
information to be transmitted.
data compression The elimination of empty fields, redundancies, and gaps in order to reduce storage
capacity needs and the amount of data to be transmitted. Anything that is eliminated is
restored after the data is received.