Differences here are not that hard to understand. If you are in scenario, where you need to plug multiple new patch cables with length between 3 and 25 feet, it is good to know how to terminated twisted pair properly. If you have spare RJ-45 plugs, some amount of cable and the networking tool kit, it would be piece of cake.
It is critical to have correct termination of a cable at both ends of the patch cable. If the termination is poor, it can cause loss or noise in signal. It could create errors for data that has been transmitted. There are two main standards how the RJ-45 should be applied for cable termination. Those standards are TIA/EIA 568A and TIA/EIA 568B. Those standards have no functional differences, however, network should have all the cables in it terminated following just one of the standards. The pin numbers and assignments for both standard terminations can be found in Figure 1.
When both ends of the cable are terminated using the same standard, the cable is called a straight-through cable. This type of cable is used to connect devices in the network and send signal “straight through”. However if one side of the cable is having TIA/EIA 568A and another one is having TIA/EIA 568A it does not mean cable is broken. This type of cable is called crossover cable and it can be used for direct connection between two workstations, or to connect two hubs through the data port. As seen from Figure 2, only two pairs have changed their pins for this cable.
Figure 2. RJ-45 terminations on crossover cable.
Three main tools are necessary for making terminations for the twisted pair: wire cutter, wire stripper, and crimping tool. However, there are tools that combine all three in one. The most difficult part of making cable is crimping, which require practice before it can be done correctly.
Wire cutter is necessary to make clean cuts at both ends of the cable. Next, the wire stripper is used to remove the shealth from the wires beginning and ending. The amount of shealth removed should be around 1 inch / 2.5 cm. Four wire pairs inside should be separated and each wire straightened. Based on the Figure 1, wires should be aligned and cleanly cut at the length of 0.5 inch / 1.25 cm. Now wires should be fully inserted into their positions in the RJ-45 in the same order that shown in Figure 1. Using crimping tool, crimp the wires into place. Each pin should be in contact with a wire. After both ends are crimped cable can be used for testing, to ensure there is no errors or data loss. Tests could be done with cable tester which comes with most networking tool kits.
