Nortel Networks 10292FA User Manual
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Glossary
212257-B
loss budget
The amount of optical power launched into a system that will be lost through
various mechanisms, such as insertion losses and fiber attenuation. Usually
given in dB.
MAN
metropolitan area network
A MAN consists of LANs interconnected within a radius of approximately
80 km (50 miles). MANs typically use fiber-optic cable to connect LANs.
margin
The amount of loss, beyond the link budget amount, that can be tolerated in a
link.
MMF
multimode fiber
A fiber with core diameter much larger than the wavelength of light
transmitted that allows many modes of light to propagate. Commonly used
with LED sources for lower speed, short distance lengths. Typical core sizes
(measured in microns) are 50/125, 62.5/125 and 100/140.
mode
An independent light path through an optical fiber. See SMF and MMF.
multimode fiber
See MMF.
multiplexing
Carriage of multiple channels over a single transmission medium; any process
by which a dedicated circuit can be shared by multiple users. Typically, data
streams are interspersed on a bit or byte basis (time division), or separated by
different carrier frequencies (frequency division).
MUX
multiplexer
A device that combines two or more signals into a signal composite data
stream for transmission on a single channel.