But the arrangement of lines inside can be changed to two functions.
The following is the specific transfer ~
Well, I suggest you take the network cable to the computer city to ask about your situation.
People over there will solve it ~ you can look at the bottom if you want ~ but you don't have the tools to change back if you are wrong.
Practical Guide for the Production of Twisted Pair Network Cables (Ⅱ)
2. Three connection sequences of twisted pair
In the actual construction, we found that there are many environments for the connection of network cables. Here are some common ones:
(1) 10M network card-10M network card as peer-to-peer network; (2) 100M network card-100m network card as peer-to-peer network; (3) 10M network card-100m network card as peer-to-peer network; (4) 10M network card-10M hub/10M, 100M adaptive hub/100m hub; 5) 10M, 100M adaptive network card-10M hub/10M adaptive hub/pure 100M hub. What should I do with this network cable?
Let's take a look at the normal twisted-pair network connection, that is, connect the network card to the hub or switch: align the plugs at both ends of the cable, and you can clearly see that the arrangement of each pair is consistent from left to right. See the figure below.
There are two international standards for normal network connection sequence, namely TIA/EIA568 mentioned by the author earlier. Let's take a look at how they are connected first.
In fact, there is no essential difference between the standard connection T568A/T568B, only the color difference. Users should pay attention to that when connecting two crystal heads, they must ensure that:
The 1 2 pair is a winding pair.
3, 6 pairs are a winding pair.
4, 5 pairs are a winding pair.
7, 8 pairs are winding pairs, which is the key.
Of course, we should also pay attention to: Don't use T568A at one end of the cable and T568B at the other end, only one specification can be used, otherwise it will become the jumper mode to be introduced later, and T568B wire pressing method is widely used in engineering.
4/5 and 7/8 wires in twisted pair are undefined. However, in concrete construction, 1, 2, 3 and 4 are often inadvertently connected (NOVELL network was connected to 10M network in this way a few years ago, but 10M network has a relatively narrow bandwidth and good connectivity, so it is also connected to 1, 2, 3 and 4. Because of the high bandwidth of 100M, the connections 1, 2, 3 and 4 can't work well. Unfortunately, the failure is manifested in different aspects: after some computers are connected, the indicator lights on the network card and hub/switch are normally lit; On some computers, the indicator light on the network card is always on, while the indicator light on the hub/switch side is flashing, which increases the difficulty of debugging. So we must attach great importance to this mistake.
T568A/T568B is a special connection mode of jumper. After the "mismatching" connection, the arrangement of wire pairs at both ends of the cable is somewhat different because the wire pairs have been bridged. This connection makes the network card and the network card form a mutual hub connection.
1 and 3 switch because the (+) output at one end must correspond to the (+) input at the other end; The reason for switching between 2 and 6 is that the (-) output at one end must correspond to the (-) input at the other end, and finally the left 1/2 pair (TX transmitter) is connected to the right 3/6 pair (RX receiver). Therefore, in the absence of HUB transfer, the correct connection of RJ45 plug should use 1, 2, 3, 6, where 1, 2 is a pair of wires, and 3, 6 is a pair of wires. This connection method must be adopted for the dual network card connection between PCs. This special connecting line that can play a pivotal role is the "wrong pair" treatment, and of course some people use 1, 6. Actually, it's ok, but it's negative. It doesn't matter whether the Manchester code is positive or negative, but it may be bad for the network card.
However, the connection between two hubs cannot be generalized (I found that many articles did not analyze this problem specifically, but summarized it in a cage and concluded that mixed wiring should be adopted). In fact, there are two ways to connect hubs: cascade and stack. The stackINg method is to use the stacking line provided by the manufacturer when buying hubs at a short distance (generally not more than 1 m), and connect it from the in port of one hub to the OUT port of another hub on the back of the hub. At this time, it is necessary to use staggered lines to connect. However, sometimes in the installation process, due to the long physical distance between the two hubs/switches, we have to connect them in cascade (mainly through the upstream port on the hub), but the cascade length between the hubs of 100Base-TX cannot exceed 5 m. The maximum distance between two switches in 100M Ethernet is 100 m ... Therefore, when interconnecting hubs in cascade mode, the following principles must be followed: when one hub uses the upstream port, the other hub/switch uses the ordinary port (except other ports which are internally connected with the upstream port and occupy the 1 port). When both hubs/switches use uplink ports or ordinary ports, the plugs of the connecting wires should be switched, that is, 1, 2, 3, 6 at one end, and 3,6, 1, 2 at the other end (that is, 1, 3 interchanged, 2,6 interchanged). For hubs/switches, after using the uplink port, 1 port (usually the uplink internal transit, that is, 1, lines 3 and 2, 6 are exchanged inside the hub/switch) can no longer be used as a public interface.
However, some people can surf the Internet when using jumpers, and they can also connect hubs in stages when using correct wiring. This is because the hub they use is a smart hub. This equipment can automatically adjust the winding of wiring. But this does not mean that the line order of this line pressing is correct. Crossover lines are lines used between two public ports, two uplink ports or these two network cards.
The two computers are directly connected through Category 5 cables, without a hub/switch. At this time, it should be noted that the plugs at both ends of Category 5 cable should be switched between 1, 3, 2 and 6. It can be seen that the interconnection between similar networked devices (such as the same port between computers or hubs/switches) needs to be switched on 1, 3, 2 and 6 lines, but different networked devices do not need to be switched.
"Wrong-right" cables are widely used. Generally, there are two computers at home that can be connected in this way, just like pulling a telephone line, and the two computers can achieve the purpose of sharing resources (without Hub). In order to play online games with neighbors, you can pull a line like this to your neighbor's house! It is also interesting to build this kind of home LAN by yourself.
If there are the above three kinds of network cable connections, which are suitable for different situations, then the last one I want to mention is the real wrong connection, that is, 1 and 2 are a pair, 3 and 4 are a pair, 5 and 6 are a pair, and 7 and 8 are a pair. Generally, this is a completely layman's connection, but the network actually uses 1, 2 and 3,6 instead of 3,4. This wrong wiring directly leads to the inability to check with naked eyes or multimeter, because its end-to-end connection is normal. Finally, the biggest harm of this wrong wiring is that it will produce great near-end crosstalk. It will not make the network impassable, but make the network run very slowly and intermittently. It's a soft fault. It's very troublesome to check when the network is running. So no matter what kind of application, this connection will not work.
Here we can clearly answer the initial question. These connections are standard UTP cable connections whether you use them in10m network or100m network. That is to say, there is no difference between 10 and 100 m. Only the HUB of 10M can be connected with the HUB of 100M. Either way, 10Base-T and 100Base-TX must be connected through a switch. Similarly, the 10M RTL8029AS(PCI) network card cannot be connected with 100MHUB. In addition, if the network cable is connected from the ordinary port of 100M to the upstream port of 100 m, 100mHUB must? It is two-speed, that is, 100M and 10M are adaptive.