First of all, the network cable can be used as long as the line sequence at both ends is the same. Short-distance use basically has no effect, but long-distance use is prone to signal attenuation, data packet loss, and frequent disconnection. A brief introduction.

Why should the network cable be made in accordance with the standard wire sequence
The cores of the network cable are twisted together at a certain density. When transmitting electrical signals, the electromagnetic waves radiated from each other will cancel each other, which can eliminate mutual interference, so the network cable is also called a twisted pair. It is precisely because of the twisted-pair structure of the network cable that each pair of the network cable has a different core twist, winding direction, and number of coils. Experiments show that the network cable is connected in accordance with the standard line sequence, the network cable has the least interference and the most stable transmission.

In 100M network transmission, only 4 cores are actually used, namely 1, 2, 3, and 6 cores. 1, 2 cores are used to send data, 3 and 6 cores are used to receive data, and 4 and 5 wires are spare lines. Lines 7 and 8 are telephone lines. For gigabit network transmission, 8-core network cables must be used, of which 1, 2, 3, and 6 cores are used to send data, and 4, 5, 7, and 8 are used to receive data.

In the connection method of the network cable crystal plug, two standard connection methods are defined, namely: EIA/TIA 568A and EIA/TIA 568B

T568A line sequence: 1. Green and white, 2. Green, 3. Orange and white, 4. Blue, 5. Blue and white, 6. Orange, 7. Brown and white, 8. Brown;

T586B line sequence: 1. Orange and white, 2. Orange, 3. Green and white, 4. Blue, 5. Blue and white, 6. Green, 7. Brown and white, 8. Brown

There are two connection methods for the network cable crystal plug, one is the direct connection method, and the other is the cross method. The crossover method is: one end of the network cable adopts the 568A standard, and the other end adopts the 568B standard.

The method of direct connection is: both ends of the network cable adopt 568A standard or 568B standard wiring.

The cross connection method is usually used for the network ports of the same device: such as PC network card to PC network card, HUB common port to HUB common port. That is to say, the color in the middle of the network cable as mentioned in the title should be exchanged. Since the general network cable only uses 1.2.3.6, the others can be used even if they are not connected.

The direct connection method is mainly used for the network ports of different devices: such as the PC network card to the HUB port, the HUB port to the HUB cascade port, such as computers connected to switches and routers, all use the direct connection method, that is, the T568B line sequence is mostly used. . Nowadays, when making the crystal head of the network cable, the direct connection method 568B is basically used to connect the crystal head. For short-distance use, you can use the same line sequence of the two segments of the network cable. For long-distance use, it is recommended to follow the standard line sequence.