What is a crossovercable when connecting two computers via ethernet cable?

There are 2 types of networking ethernet pinout types (there is a 3rd one called USOC, but it is used only in business phone systems, so we will not get into that)

The 2 networking ethernet pinouts are 568A and 568B, usually when you go to learn about the pinouts of an ethernet cable, you have to know about the pairs (1:Blue, 2:Orange, 3:Green, 4:Brown), as the diagram cards explaining them will display them in pairs

568A is: White/Green, Green, White/Orange, Blue, White/Blue, Orange, White/Brown, Brown

568B is : White/Orange, Orange, White/Green, Blue, White/Blue, Green, White/Brown, Brown

As you can see, the only difference between 568A and 568B is is the green pair and the orange pair are switched, this is because the blue and brown pairs are for grounding only, and usually not required, if I remember right, the orange pair is send, and the green pair is recieve

Using those pinouts, there are 2 major kinds of ethernet cables we use, a pass through cable, and like you mentioned, a crossover cable, these are the pinouts of each

Pass Through (Modem to Router, Router to switch/hub, switch/hub to computer)

End 1: 568B (in some rare cases, 568A)

End 2: 568B (in some rare cases, 568A)

Must be the same pinout on both ends

Crossover (To like devices, computers to computers, hubs/switches to hubs/switches)

End 1: 568A

End 2: 568B

Must be a different pinout on each end

To spot a crossover, look at the top of the connector (the part with the 8 connectors), one should start (from the left) with White/Orange, the other should start (from the left) with White/Green

An ethernet cable is a normal cable typically used to connect a computer to a router/modem for internet. A crossover cable is the same thing as an ethernet cable but with 4 of the wires flipped over. A crossover cable is used to connect 2 of the same type of devices. For instance, if you want to connect your PC to a router, you would need to use a ethernet cable because a crossover cable wouldn't work. If you wanted to connect 2 computers together, you would need to use a crossover cable, because an ethernet cable would not work.

Usually, to connect two computers together you would use a router or a switch. A crossover ethernet cable connects two PCs directly so they can communicate with each other without the need of routers etc.

http://en.wikipedia.org/wiki/Ethernet_crossover_ca...

Most new routers/switches can tell the difference and adapt so you can use them interchangably with normal network cables anymore. The exception is connecting 2 PCs without any other hardware, which requires a crossover cable.