Paradyne 3821PLUS manual Iso

Glossary

handshaking	The exchange of predetermined codes and signals (tones) to establish a connection
	between two modems.
HDLC	High-level Data Link Control. A communications protocol defined by ISO.
host	A computer attached to a network that shares its information and devices with the rest of
	the network.
Hz	A unit of frequency (hertz) that equals one cycle per second.
ISO	International Organization for Standardization.
ITU-T	The Telecommunications Standardization Sector of the International
	Telecommunications Union, an advisory committee established by the United Nations to
	recommend communications standards and policies. Before March 1993 it was called
	CCITT.
JM8	A jack used for leased-line networks. Pins 1 and 2 are the transmit pair and Pins 7 and 8
	are the receive pair.
LCD	Liquid Crystal Display. The device that permits text to be displayed on the DCP or
	SDCP.
leased line	A private line connection exclusively for the user. No dialing is necessary.
LED	Light-Emitting Diode. A light or status indicator on the DCP or SDCP that glows in
	response to the presence of a certain condition (e.g., Alrm).
local analog loopback	Test in which the modem's transmit VF signal is looped to its receiver.
long space disconnect	A disconnect can occur if the modem receives an extended space from a remote modem;
	for example, when a remote modem is commanded to disconnect, it transmits a
	continuous space to the modem before disconnecting.
loopback test	Any test that verifies a device's integrity by connecting the device's output of one
	direction to the device's input of the other direction, then checking the received signal
	for errors.
LSD	Line Signal Detect. A signal between the DTE and modem indicating energy exists on
	the transmission circuit.
MNP	This protocol (Microcom Networking Protocol) detects and corrects data errors caused
	by telephone line noise and signal distortion. MNP5 includes data compression.
modem	MOdulator/DEModulator. A device that transforms signals from digital to analog form
	and vice versa.
modulation	The process of varying some characteristics (usually amplitude, frequency, and/or phase)
	of a carrier wave to form data transmissions.
off-hook	The state of a telephone or modem that is being used.
on-hook	The state of a telephone or modem that is not being used.

3821-A2-GB20-40 January 1999 Glossary-5