What type of connectivity is a "crossover cable" used for?

A crossover cable is specifically designed to connect two similar devices directly, such as connecting one switch to another switch, or connecting two computers without the need for a hub or switch. This type of cable is wired differently than a standard Ethernet cable, allowing it to transmit signals from one end to the other in a way that matches the pin configurations necessary for peer-to-peer communication.

The crossover wiring means that specific pairs of wires on one end are crossed over to a different pair on the other end, ensuring that the transmitting signals from one device line up with the receiving signals on the other device. This makes crossover cables suitable for creating direct connections where both devices could otherwise not communicate effectively, making it essential for setups that do not involve intermediary networking devices.

For other options, a computer to router connection typically uses a straight-through cable, as does a modem to switch connection. Connecting devices through a firewall generally involves different kinds of configurations beyond just cable types.