26-01-2012, 03:58 PM
Optical networks
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INTRODUCTION
Explosive information demand in the internet world is
creating enormous needs for capacity expansion in next generation
telecommunication networks. It is expected that the data- oriented
network traffic will double every year.
Optical networks are widely regarded as the ultimate solution
to the bandwidth needs of future communication systems. Optical
fiber links deployed between nodes are capable to carry terabits of
information but the electronic switching at the nodes limit the
bandwidth of a network.
OPTICAL FIBERS
A fiber consists of a glass core and a surrounding layer called
the cladding. The core and cladding have carefully chosen indices of
refraction to ensure that the photos propagating in the core are always
reflected at the interface of the cladding.
OPTICAL SWITCHES
Optical switches will switch a wavelength or an entire fiberform
one pathway to another, leaving the data-carrying packets in a
signal untouched. An electronic signal from electronic processor will
set the switch in the right position so that it directs an incoming fiber –
or wavelengths within that fiber- to a given output fiber. But none of
the wavelengths will be converted to electrons for processing.
