How to Create “Crossover Cable” and “Direct Cable”
If you have two or three computers at home or in your office, surely you have an interest in connecting them in a network to share printers, files and Internet connection. For this, the most common is the creation of a crossover cable or a straight through cable. This tutorial will teach you how to create them.
In this tutorial, the DigoPaul will make use of the following items to the fitting (or crimping) of the cables crossover and straight:
– Pliers for crimping;
– RJ-45 connectors;
– UTP cable standard CAT 5 (size variable according to with the need).
The pliers crimp is used to hold the ends of the cord UTP to RJ-45 connectors. These, in turn, are connected to the the computer’s network adapter or hub/switch.
Cable crossover or straight through cable?
When we want to assemble a cable to connect two computers, not we need to use devices such as hubs, since you can connect a machine to another directly. In this case, the cable type “crossover” (cross-over or inverted) must be used.
On the other hand, when three or more computers must be interconnected, equipment such as the hub shown ideal. In this case, it is necessary to to create a cable to each computer and connect them to the hub. However, the cable type crossover does not serve this purpose, and shall be used the cable type “straight”, also known as a “patch cable”.
In summary, to connect computer to computer using crossover cable. To connect the computer to the hub, use direct cable. The difference between the they is that the crossover cable has the disposal of his wired differently on a tip in relation to the another, while the direct cable has the layout of the wires equal at each end.
OBS.: the crossover cable should also be used when it is need to connect one hub to another.
A little more on the cable
The UTP cable is one of the most used for the creation of computer networks based on wires. Its development was the result the work of the Electrical Industrial American (EIA) and Telecomunications Industrial American (TIA), who have researched the development of a means efficient communication networks. After this definition, the Bell Laboratories worked on the development of the UTP (Unshilded Twisted Pair).
In the networks the Ethernet standard are practically only used cable UTP CAT 5. This means that this type of cable is composed for four pairs of wires and operates at the frequency of 100 MHz.
The photo below shows the pairs of wire. Notice that they are combinations of the colors orange, blue, green, and brown with matching white in color. Thus, a wire in blue color has as a pair a wire in the colors of blue and white. A wire in green color has as a pair a wire in the colors green and white, and so forth:
It is more common to find cables UTP jacket colour blue, however, it is not difficult to find cables in the other colors.
Riding the cable direct
The first step to assemble the cable consists of taking part of the coating (approximately 1 cm) of the ends of the cable, leaving exposed wires. For this reason, you should use cutting pliers (some pliers crimping come with this feature, as the template used in this tutorial), but take be careful not to cut the wires. Then, you should put them in the following order:
This sequence is known as the standard EIA/TIA 568A.
After the realization of this step, it is necessary to fitthe RJ-45 connector, taking care to make each wire between in the corresponding hole. To do this, hold the connector firmly on the one hand and the tip of the cable in the other. Insert the wires slowly, making sure that none went the same way. If when you reach the end the connector you notice that any wire has some difference size or is further back in relation to the other, redo the procedure. The wires must have the same size and everyone must get to the end of the holes of the connector.
It is very important that the coating of the cable between in the connector. Otherwise, it will be more easy to occur the breaking of the wires. The figure to the aldo shows this situation.
After you make sure that the cable is properly inserted in the connector, it is time to crimpar. To do this, place the connector inside the corresponding space of the pliers, crimping (refer to the sheet instructions that came with your product to make no mistake). Hold the cable with one hand and with the other press the pliers. After the cable to be relatively stuck, strengthen the procedure by tightening the pliers with the two hands. Tighten well, but take care not to overdo it and damage the connector.
If you notice any problem after crimpar the cable, not it will be possible to take the connector. The output is cut the cable at this point and repeat all steps.
The straight through cable has both ends the same, just simply repeat the procedures above to the other end. If everything works out your straight through cable is ready to be used!
Riding the cable crossover
The crossover cable must have one end on the standard EIA/TIA 568A. Soon, do the procedures of the previous topic in one of the sides of the cable.
Done this, on the other end, it is necessary that the wires are placed in the RJ-45 connector in the following order:
This sequence is known as the standard EIA/TIA 568B.
Completed these steps, the crossover cable will be ready to use.
The first few times you crimpar a cable, surely you will feel some difficulty. It is possible that you have to that redo a few steps. If this occurs, do not worry, it is normal. With practice, you will master the subject quickly.
Finally, here is a tip: if you go the do crimp cables frequently, it is advisable to use a device known as a cable tester. In it, you connect the ends of the cables and the instrument will indicate if the cable is perfect or if it has some flaw. There are several models of these devices, so look for a specialty shop to choose a that you meets. Good job!!!