A fiber optic cable is a network cable that contains strands of glass fibers inside an insulated casing. They're designed for long-distance, high-performance data networking, and telecommunications. Compared to wired cables, fiber optic cables provide higher bandwidth and transmit data over longer distances. Fiber optic cables support much of the world's internet, cable television, and telephone systems.
Fiber optic cables consist of one or more strands of glass, each only slightly thicker than a human hair. The center of each strand, called the core, provides a path for light to travel. Surrounding the core is a layer of glass called the cladding, which reflects light inward to avoid signal loss and allows light to pass through bends in the cable.
There are two main types of fiber optic cables: single-mode and multimode. Single-mode fiber uses extremely thin strands of glass and lasers to generate light, while multimode fiber optic cables use LEDs.
Single-mode fiber optic networks typically use wavelength division multiplexing to increase the amount of data traffic a fiber strand can carry. WDM allows multiple different wavelengths of light to be combined (multiplexed) and subsequently separated (demultiplexed), effectively transmitting multiple communications streams over a single pulse of light.
Fiber optic cables have several advantages over long-distance copper cables.
Fiber optics support higher capacity. The amount of network bandwidth that fiber optic cables can carry easily exceeds that of copper cables of similar thickness. Fiber optic cables rated at 10 Gbps, 40 Gbps, and 100 Gbps are the standard.
Because light can travel longer distances through fiber optic cables without losing its strength, the need for signal boosters is reduced.
Fiber optic cables are less susceptible to interference. Copper mesh cables require shielding to protect them from electromagnetic interference. While this shielding helps, it is not enough to prevent interference when many cables are strung together close to each other. The physical properties of fiber optic cables avoid most of these problems.