VeEX MPA, Руководство пользователя

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L
814
Suffix indicating line level.
LAN
Local Area Network. A LAN typically connects workstations, peripherals, terminals, and
other devices in a single building, campus, or other geographically limited areas. LAN
technologies usually employed include Ethernet, FDDI, and Token Ring. LANs are
usually not subject to public telecommunications regulations.
Large LEDs
A common function tab that displays LED Error and Alarm indicators in a large, easy-to-
read format, which covers the entire touch screen area.
Laser
An acronym for Light Amplification by Stimulated Emission of Radiation. A device which
is able to produce light at a single frequency and phase. Light that has a single
frequency and a single phase is said to be coherent, in contrast to normal light which
has multiple frequencies and random phase combinations. The waves of non-coherent
light can be likened to a crowd of people rushing down the street in contrast to coherent
light which in the same example, is more like a group of soldiers marching down the
street in row formation with each soldier in step.
LCV
Line Code Violation. A signal error in the physical layer of an electrical link.
LFD
Loss of frame delineation. Frame delineation is lost whenever multiple bit errors are
detected in the Core Header by the cHEC. In this case, a GFP Loss of Frame
Delineation event is declared.
Lightwave
Refers to the use of light as a communication signal when transmitted over fiber-optic
cable. Light itself can travel over distances as a wave of energy, hence lightwave. The
light signal communication travels as a discrete series of pulses of light.
Line
A line is a transport entity that provides the means of moving a digital signal between
two consecutive NE (Network Elements) - one originating the line signal and the other
terminating it. A SONET network Line comprises the transmission medium, together
with the associated equipment, and provides the means of transporting information
MPA_e_manual_D07-00-129P_RevA00