As we all know, the cable has a light weight, small size, long transmission distance, large capacity, small signal attenuation, anti electromagnetic interference and other advantages, has been widely used network. With the development of the 21st century, fiber optic cable has already become our country network data transmission, network communications, cable radio and television and other special subject, in the choice of twisted pair cable, coaxial cable, by visual inspection and simple testing can largely determine the performance advantages and disadvantages, and the choice of the fiber optic cable is not so simple, as compared with the twisted pair cable, coaxial cable, not only the structure is complex, a variety of materials, in addition to the existing parameter and many potential factor, such as materials, production process and equipment in many aspects, assuming slightly accidentally thirty years of life is difficult to ensure that is several years of technical parameters may not be up to the standard. Therefore, we are in the construction of the network, it is to the structure of the optical cable, materials, processes, and other aspects of a profound understanding and understanding, in order to choose the appropriate model of the cable. Below by the fiber optic cable manufacturers to you to break down three ways to buy the cable 1 according to the use of the choice of optical cable The cable can be divided into overhead cable, buried cable pipe, cable, submarine cable and metal free cable etc.. Aerial cables require high strength, small temperature coefficient; the requirements of anti buried, compression, moisture and humidity are particularly good buried cable, chemical corrosion resistance; undersea fiber optic cable and optical cable pipeline is to water resistance, resistance to tension, good waterproof performance; non metal optical cable and high tension line with erection, insulated, although there is no ferrite core, but also to the tensile ability. Therefore, in the purchase of optical cable, the user to choose according to the use of the optical cable, and manufacturers of the requirements, to ensure that the use of stable and reliable cable. 2 select the cable according to the number of cores Several core number choose different types of cable structure can be classified as the center beam tube type, stranded, skeleton and strip type, different uses different structure, users can according to the conditions of the line are put forward the corresponding request. General 12 core following is the use of the central beam type. Central beam tube type process simple and low cost, in overhead wear design or have a good pipeline protection feeder network in competitive; layer stranded optical by central placed single strand steel wire strengthening, adopting SZ continued synthetic fiber optic cable, fiber cable into a number up to 144 cores. Its biggest advantage is waterproof, anti tensile strength, strong lateral pressure can be for direct buried also easy to bifurcation, even partial optical fiber and cable need to separate the use, will certainly not the whole cable is disconnected, only need to will be bifurcated fiber optic cable disconnect can, which for data communication network, cable TV network along the addition of festival of light is advantageous; number of the ribbon cable core can do thousands of core, it is will be 4-12 core optical fiber arranged in rows, constitute a ribbon fiber unit, and then a number of strip elements in a certain way are arranged in a cable. Our network level cable is generally used in beam tube and layer two can be.