Ethernet cable, receive, send each by a pair of twisted-pair bear, for the two connected devices, to do to send and receive the corresponding to work properly. Ordinary Ethernet cables are commonly used straight lines, the two are exactly the same. It is generally used for connections between network devices and terminal devices (such as switches and computers), since their definition of sending and receiving is just the reverse. An Ethernet crossover cable is a crossover line, where 1, 2, and 3 and 6 are cross-linked. Used for connections between similar devices (such as computers connected to computers, switches, etc.), because their definitions are the same, with cross-line to send and receive correspondence. However, many devices now have automatic reverse function, in most cases can be directly connected.
The difference between direct-connect cable and crossover cable in computer network