How much data is lost in a optic fiber?

Question

How much data is lost in a optic fiber?

Answer 1

none, unless the cable is defective.

There is attenuation over distance, just as there is with electrical signals, and similarly, repeaters are added at fixed distances to reconstitute the signal.

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Answer 2

Data is not lost through fibre, light is. Do you mean what is the packet loss ?

Transmission of data / light by fibre optics is not 100% efficient.

There are several reasons for this including absorption by the core and cladding (caused by the presence of impurities) and the leaking of light from of the cladding.

When light reflects off the cladding /core interface it actually travels for a short distance within the cladding before being reflected back. This leads to attenuation (signal reduction) by up to 2db/Km for a multi-mode fibre.

For example, with this level of attenuation, if light travelled over 10kM of cable only 10% of the signal would arrive at the following end. The amount of attenuation for a given cable is also light source, wavelength and physical cable properties dependent.