Net refers to the three major networks of Telecom Network, Radio and Television Network and the Internet. The three networks are the existing, independent, independent traditional telecommunications networks, computer broadband networks, and limited television networks to achieve mutual penetration and unity. In the end, a variety of services are used in a separate network. The physical link is presented to the information consumption. Therefore, the three networks and one network system have the following characteristics:

(1) Users only need a physical network connection to enjoy other network resources or communicate with users on other networks.

(2) The network is interoperable in the physical layer, which means that the signal of a network can be transmitted directly or through the organization or transformation to be transmitted to another network. When transmitting to the user terminal through another network, the information does not change the information. The content, that is, the network should be transparent.

(3) The business between the network penetrates and cross the application layer, but they can be independent and unhindered by each other, and they can develop their own new businesses independently on their respective networks.

(4) The agreement between the network is compatible with or can be converted. This is because each network has its own agreement, so when the information is transmitted from one network to another, it should meet the requirements for the transfers to the network.

When the three networks are achieved, we will definitely use the three -screen optical fiber wiring rack. What is the three -net combination and one optical fiber wiring rack? What is its role?

The crystal head plastic port is relatively strong. We can simply judge that the crystal head is hollowed by hand. If there is a more obvious deformation, then there is a problem with the quality of its quality; however It is quite good. You can try to turn it back. Generally, you can easily bend about 180 degrees without breaking. After loosening, there will be no deformation.

       If the appearance conforms to the above phenomenon, it means that the quality of the crystal head is still excellent. Some of the materials made of crystal head contain impurities, and the plastic sheet is broken or deformed after bending, then it shows that its quality is very problematic.