Lucent Technologies DDM-2000 OC-3, Руководство по установке

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GLOSSARY
Issue 9 October 1998 GL-11
J
Jitter
Timing jitter is defined as short-term variations of the significant instants of a digi-
tal signal from their ideal positions in time.
L
LAN
Local Area Network.
LAPD
Link Access Procedure "D".
laser
A semiconductor device. Used on a circuit pack as a source of coherent light for
communications.
LBO
Line Build Out — An equalizer network between the DDM-2000 Multiplexer and
the DSX panel. It guarantees the proper signal level and shape at the DSX panel.
See also, optical LBO.
LCN
Local Communications Network.
LED
Light Emitting Diode — A semiconductor device. Used on a circuit pack or shelf
faceplate to show failure (red) or service state. It is also used to show the alarm
and status condition of the system.
Local
See NE (Near-End. )
LOF
Loss of Frame — A failure to synchronize to an incoming signal.
Line Timed
A timing mode in which the terminal derives its transmit timing from the received
line signal. Formerly called “loop timed”.
Loop Timed
The former name for line timed.
LOP
Loss of Pointer — A failure to extract good data from an STS-1 payload.