The fiber optic cable core is the physical glass medium that transports optical signals from an attached light source to a receiving device. A TOSLINK optical fiber cable with a clear jacket. These cables are used mainly for digital audio connections between devices. 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. A fiber optic cable consists of five basic components: the core, the cladding, the coating, the strengthening fibers, and the cable jacket. Optical fibers operate on the principle of total internal reflection, which keeps the light in the fiber core and guides it down the length of the fiber.