CAT5e PINOUTS AND Wiring DIAGRAMS
Straight through cables are used to connect a computer to a hub or switch. If your connection is PC to PC or Hub to Hub then you must use the crossed standard.
The following diagrams shows the colour coding for CAT5e cables based on the two standards supported by TIA/EIA. 568B wiring is by far the most common wiring method. There is no difference in connectivity between 568B and 568A cables, so you can choose the method that suits you best providing that both ends of the cable uses the same standard.
Crossover cables are used to connect PCs to one another or to connect a hub to hub. However, most hubs these days have an uplink port which allows you to connect to hubs together through this port using a straight connection, you should read your hub manual to check if it has this.
The following diagram shows the wiring at both ends of the connectors. It shows crossing of all four pairs.
Below is a diagram of the RJ45 connector and pin numbers so you can see which pin numbers relate to the diagrams above.
