Optical fibers come in two types:
Single Mode
Single-mode fiber is used for longer distances due to the smaller diameter of the glass fiber core, which lessens the possibility for attenuation — the reduction in signal strength.
The smaller opening isolates the light into a single beam, which offers a more direct route and allows the signal to travel a longer distance.
Single-mode fiber also has a considerably higher bandwidth than multimode fiber.
-mode fibers
Multi-mode
Multimode fiber is used for shorter distances because the larger core opening allows light signals to bounce and reflect more along the way.
The larger diameter permits multiple light pulses to be sent through the cable at one time, which results in more data transmission.
there is more possibility for signal loss, reduction or interference,
