O ptical f iber Transmission media are the physical way that device can connect on network, T ransmission media divided into two parts wired and wireless.each of them have its on types The optical fiber or fiber optic is one of the most popular and used for transferring data throw content Optical Fiber Anatomy Core : The glass or plastic center of an optical fiber. Cladding : Glass or plastic surrounding the core of an optical fiber; the optical density of the cladding must be less than that of the core. Optical fibers use reflection to guide light through a channel. The difference in density of the two materials must be such that a beam of light moving through the core is reflected off the cladding instead of being refracted into it. The composition of a typical fiber-optic cable The outer jacket is made of either PVC or Teflon. Inside the jacket are Kevlar strands to strengthen the cable. Kevlar is a strong