Optical fiber

An optical fiber is a transparent thin fiber, usually made of glass or plastic, for transmitting light. Fiber optics is the branch of science and engineering concerned with such optical fibers.

Advantages of optical fibers over wires

• Lower cost in the long run
• Low loss of signal (typically less than 0.3 dB/km), so repeater-less transmission over long distances is possible
• Large data-carrying capacity (thousands of times greater, reaching speeds of up to 1.6 Tb/s in field deployed systems and up to 10 Tb/s in lab systems)
• Immunity to electromagnetic interference, including nuclear electromagnetic pulses (but can be damaged by alpha and beta radiation)
• No electromagnetic radiation; difficult to eavesdrop
• High electrical resistance, so safe to use near high-voltage equipment or between areas with different earth potentials
• Low weight
• Signals contain very little power
• No crosstalk between cables
• No sparks (e.g. in automobile applications)
• Difficult to place a tap or listening device on the line, providing better physical network security