If you are using fast ethernet, all the pairs are used (half for transmitting and half for receiving). Pointing an RJ-45 plug at you and looking from above with the contacts on top, pin one starts on the right and pin 8 is on the left. If you are using standard 10 mb/s ethernet, then the blue (pin 4), blue/white (pin 5), brown/ white (pin 7), and brown (pin 8) are unused. Green/white (pin 3) and green (pin 6) are used for receiving; orange/white (pin 1) and orange (pin 2) are used for transmitting. If you are using an uplink port, then you don't want to swap any of the wires, this is done internally by the device with the uplink port. It assumes you are using a straight-through wiring scheme. Make sure your wiring between the wall plate and the RJ-45 connector on the other end where the hub or switch is has contiuity in the same places (on the same colors/colours) as a verified working patch cable has. If not rewire the wall plates to match. Also make sure your wire run is no more than 330 feet and doesn't run parallel to any electrical wires.