How to create a crossover cable
By Joshua Erdman
The Crossover Cable allows you to connect two computers directly together by their network cards without using a hub or switch. This type of cable is also needed when connecting a hub or switch together that do not have an uplink port. It is usually made from scratch. It is called a 'crossover cable' because the transmit and recieve pairs are switched (or crossed) at one end.
Creating a crossover cable
To make a crossover cable, you use two different wiring orders for each end. On one end use the standard color order: White/Orange-Orange,White/Green-Blue,White/Blue-Green,White/Brown-Brown (See picture on the right).
Clue: It doesn't really matter what you do with the brown and blue pairs since only the orange and green pairs are used for standard network data transmission.
For the other end, switch the location of the orange and green pairs (so you switch white-orange with the white-green, and switch the solid orange with the solid green giving you the color order: White/Green-Green,White/Orange-Blue,White/Blue-Orange,White/Brown-Brown).
This connects the pair that the computer transmits over to the recieve end on the other computer and vice-versa.
Clue: You cannot use a crossover cable to connect a computer to a hub or switch. You can only use standard network patch cables for this. Crossover cables are only designed to connect two hosts directly together or to connect two network management devices (such as a hub or switch) directly together when an uplink port is not available.
You can read our network termination article for more information on network wire color orders and also wire types.
Network Wiring Tools & Hardware Needed
Read The Administrator's Ultimate Toolkit Article for good ideas on tools and where to buy them.
Article last reviewed: 06/27/2004