Alcatel-Lucent Data Multiplexer Explore 1665, Руководство по установке

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365-372-304R7.1
Issue 1, November 2007
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Holdover
An operating condition of a network element in which its local oscillator is not locked to any
synchronization reference but is using storage techniques to maintain its accuracy with respect to the last
known frequency comparison with a synchronization reference.
I IC - Internal Clock
Used in synchronization messaging.
ID
See shelf ID and site ID.
IR - Intermediate Reach
A term used to describe distances of 15 to 40 km between optical transmitter and receiver without
regeneration. See long reach.
IS - In Service
One possible state of a DS1, DS3, or EC-1 port. Other possible states are "auto" (automatic) and "nmon"
(not monitored).
J Jitter
Timing jitter is defined as short-term variations of the significant instants of a digital signal from their ideal
positions in time.
L LBO - Line Build Out
An equalizer network between the DMX 2.5G Multiplexer and the DSX panel. It guarantees the proper
signal level and shape at the DSX panel.
LED - Light Emitting Diode
Used on a circuit pack faceplate to show failure (red) or service state. It is also used to show the alarm and
status condition of the system.
Line Timing
The capability to directly derive clock timing from an incoming OC-N signal while providing theuser the
capability to provision whether switching to an alternate OC-N from a different source (as opposed to
entering holdover) will occur if the OC-N currently used as the timing reference for that NE becomes
unsuitable as a reference. For example, intermediate nodes in a linear network are line timed. See Loop
Timing.
Local
See Near-End.
Locked Cross-Connection
This is a variation of the ring cross-connection that allows the user to lock the path selector to a specified
rotation of the ring. Any signal received from the other rotation of the ring is ignored.
LOF - Loss of Frame
A failure to synchronize to an incoming signal.