Physical layer - Optical fiber medium

Optical fiber is one of the three types of physical media used for the transmission of information in data networks. Fiber optics are cables that are composed of a core of glass surrounded by various layers of insulation and protective sheaths. Information is transmitted over the cable in the form of pulses of light.

Advantages of fiber optics include:

  • faster transmission speeds
  • zero interference from electromagnetic sources
  • extremely long transmission distances on the order of several hundred meters to dozens of kilometers
  • very long lifetime on the order of several decades

Disadvantages include:

  • more expensive than other media types due to the cost of:
    • materials and manufacturing process
    • devices and electronics required to send and receive light pulses
    • specialized installation procedures
  • more difficult to install due to comparatively fragile nature of the medium

For more information on optical fiber, take a look at: