Types
Two different wirings exist : a type A and type B both under the standard EIA/TIA T568.
A streight through cable has on both sides of the cable the same type, so A-A or B-B.
A cross cable is a cable which has on one side a type A and on the other side a type B.
The 'crossing" nature comes from the different wirings between the A and B types.
Pin numbering
The male plug is numbered with the copper leads upwards and pointed away from you.
The female connector matches logically to this principle so leads upwards and
Ethernet Cable
An ethernet cable exists in Shielded Twisted Pair (STP) and Unshielded Twisted Pair (UTP).
The cable is composed of a twisted bundle of four twisted pairs of wires: a green, an orange, a blue and a brown pair. Each pair is composed of a solid and white combined wire.
The shielding of the cable makes a difference in fault tolerance and guaranteed throughput.
Be aware that in case Shielding has to be used, the shielding should not only be foreseen for the cable but also in all of the other network components: the plug, the switch or peripheral ... . The 'grounding' of the shield must be foreseen and tested.
Pin to Wire Match
Type A (EIA/TIA T568A):
pin 1 : green/white (TX+)
pin 2 : green (TX-)
pin 3 : orange/white (RX+)
pin 4 : blue
pin 5 : blue/white
pin 6 : orange (RX-)
pin 7 : brown/white
pin 8 : brown
Type B ( EIA/TIA T568B):
pin 1 : orange/white (TX+)
pin 2 : orange (TX-)
pin 3 : green/white (RX+)
pin 4 : blue
pin 5 : blue/white
pin 6 : green (RX-)
pin 7 : brown/white
pin 8 : brown
For a color reference please follow this link.
Although it seems that the blue and brown sets are not used, they have a use for full duplex use of the ethernet cable ... it seems ... have not found their use ... yet ...
