Optical fiber communication is the best for transmitting data at a high rate. While the fiber channel may be capable of transmitting terabit-per-second data rates, no existing single communication system can make complete use of this speed. Optical fibers in discussion that guide signals in the form of light are typically made of from two glasses. It is a cylindrical in shape waveguide consisting of a higher refractive index solid glass core which runs down middle of the fiber. The other solid glass with a lower refractive index surrounds the core and makes the homogeneous cladding. The two glasses are made of from the common material silica. Photonic crystal fibers can be divided into two modes of operation, according to their mechanism for confinement. Alternatively, one can create a photonic band gap fiber, in which the light is confined by a photonic band gap created by the micro structured cladding – such a band gap, properly designed, can confine light in a lower-index. Here, four wave mixing technique provides operational flexibility.