The generalized network including coaxial cables, telephone lines, optical fiber and twisted pair. According to the standards set by the IEEE Ethernet, USES the star topology structure of common local area network (LAN) is the most suitable for use twisted-pair cable. Twisted-pair cable use rubber as the shell material, and the internal contains different colors of 4 to 8 copper plastic core. Every two conductor weave together according to certain rules, become a core over. It includes unshielded twisted pair (UTP) and shielding twisted-pair (STP). Shielded twisted-pair (STP) cost is high, the theory can better shielding electromagnetic signal interference, but because of its high environmental requirements for network construction, in practice we often find shielded twisted-pair (STP) and unshielded twisted pair (UTP). Starting from the performance and maintainability, now most of the local area network (LAN) using unshielded twisted pair (UTP), people usually buy cable is the unshielded twisted pair (UTP).
Internationally accepted the EIA/TIA - 568 twisted-pair cable standard divided into 3, 4, 5, 5, 6, 7, etc. 6. 3, 4 twisted-pair cable is suitable for application in the old standard of 10 MBPS network, and 5 class is currently 100 MBPS network standard products, super five types can be used in the 1000 MBPS network. And five types, such as super five types are compatible with low-level network.
We recommend that you choose and buy super five types of cables and convenient use 1000 MBPS network in the future. But there are many on the market at present with 3 or 4 class cable fake 5 classes and super five types of cable, there are also some fake. To distinguish them roughly the following several ways:
1, the quality of the packaging. The twisted-pair are boxes on the market for sale. Each box is 300 meters. The authentic twisted pair better packing carton should be material and printing more clear, and in most cases outside the carton stickers.
2, twisted pair shell's work. Twisted-pair cable insulation shall be printed with the origin of a product on the skin, standards, product category, line length and other information. 5 kinds of line identifier is cat5, five line of logo is "cat5e," six lines of logo is "cat6". And imprint on skin "CAT5" and "five e" contains uppercase letters printed products tend to be more suspicious. If you force your suspicious twisted-pair cable surface printing, is likely to put these words color rub off.
3, twisted pair can easily bend. Formal manufacturers in the production line when considering the cables need to bend, they will make in the manufacturing of twisted-pair skin more flexibility, can extend. In the production of inferior line profiteers tend to cut corners in order to save cost, the consequences of which is the network cable is difficult to recover after bending. Will a cable can be folded in half and if it can pop up original state suggests that it is genuine.
4, if there is a flame retardant skin. In order to ensure safety, twisted pair is ordinary flame point of non-combustible. With better fire lighters directly to the skin, good cable sheath will gradually melt deformation under the grill, but couldn't come.
5, twisted pair twisted way. Twisted-pair cable is not only good quality every line of twisted counterclockwise manner, and with four lines between twisted counterclockwise manner. Average ground line length is called twisted circle of the unity of density, super 5 lines to class than five types of twisted density is big, five types of wire twisted density is bigger than 3 classes. False twisted line density is small, will look more loose.
6, the color of the conductor in twisted-pair. If we remove the twisted-pair cable outer rubber, we can see the inside of the four to eight root core, they are orange, orange, white, green, white, green, white and blue, blue, white, brown and brown. Three kinds of line only four core, can only be disguised as it will be part of the core stain 8 core of five types of thread. So, fake and inferior line core force to administer it will rub off.
7, the measured home. At home between the computer and the computer through the "neighbors" online copy files, because the three kinds of line can achieve the fastest rate of LAN is 20 megabits per second (2.5 MBps), so just copy rate greater than 2.5 MBps can prove whether cable support 100 MBps network.
