Optical fiber is the medium of choice for high capacity digital transmission systems and high speed local area network. Besides these applications, optical fiber also can be used to transmit microwave signals for cable television, cellular radio, WLAN and microwave antenna remoting. To transmit microwave over optical fiber, the microwave signal is converted into optical form at the input of the fiber and at the output of the fiber, it is converted back to electrical signal. The main advantage of fiber transmission of microwave is reduced losses relative to metallic media (e.g. copper coaxial cable). This results in longer transmission distance without signal amplification or use of repeaters. One of the best things about the fiber optics is ease of installation. Unlike the other cables which are heavy and complex to establish connection, fiber optic cables are light and flexible to install. The process of installing is similar to any wire cable installation, but the method, tools and instruments require to complete the task is different. Fiber optic box networks are becoming increasingly popular among service providers. These networks also known as Fiber to the Home, Fiber to the Premise, PON (Passive Only Networks) are closed system networks. The transference of data is not transmitted through the air; it is sealed within optical cables and related network components. As with any telecommunications network it begins at a Head-end or Central Office. This is where Incoming signals of voice, video and data from satellite, microwave and off-air sources are gathered. The information is then processed, turned into light and sent through laser transmitters into the optical network cables. These cables carry the data great distances at light speed throughout the network. The light does not have to be converted until it reaches its final destination at a home or business. The conversion of light to fiber optic box and light to electrical impulse is necessary for electronic devices such as television sets, telephones and computers to understand the information. This conversion is accomplished through a small device at the home or business known as an NIU (Network Interface Unit) or sometimes called an ONT (Optical Network Terminal.)