Optical fiber is a transmission beam subtle and flexible media. Fiber optic cables consist of a bundle of optical fibers, referred to as fiber optic cable. Fiber optic cable for data transmission is the most effective one transmission medium, the advantages of its advantages similar to the optical fiber, mainly in the following areas:

1. Wide-band.

2. Good magnetic insulation. Fiber optic cable transmission is the beam, as the beam is not afraid by external electromagnetic interference and influence, and itself does not radiate signals out, so it is suitable for long-distance transmission of information and the requirements of high-security applications. Of course, the tap is its inherent difficulty of the problem, because the cut of the cable needs to be regenerated and retransmitted signals.

3. less attenuation. Over longer distances and the range signal is a constant.

4. The repeater spacing larger, it is possible to reduce the number of the channel repeaters entire cost can be reduced. According to Bell Labs testing, when the data transfer rate of 420Mbps and a distance of 119 kilometers without repeaters, transmission quality is very good. The coaxial and twisted-pair every few kilometers on the need to take a repeater.