A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube. Fiber-optic communication is a form of optical communication for transmitting information from one place to another by sending pulses of infrared or visible light through an optical fiber. Fiber is preferred. What is fiber optic attenuation? As fiber optic cables pass data, some of this data is naturally lost as it moves across great distances. How much optical power is lost is expressed as attenuation. It is reliable, versatile, and widely used in many applications and industries.