Which statement is true about crossover cables in Ethernet networking?

Which statement is true about crossover cables in Ethernet networking?

• A. They connect similar devices, such as switch-to-switch or PC-to-PC.
• B. They are the standard for all router connections.
• C. They replace the need for a switch.
• D. They are used to connect a computer directly to a wall port.

Answer: (A)

Crossover cables are used to connect similar devices by flipping the transmit and receive pairs so the devices’ send and receive paths line up. In Ethernet, end devices like PCs and NICs are MDI, while switches (and other uplink devices) are MDIX. A crossover cable swaps the TX and RX lines so data from one MDI device is received by the other MDI device, or both MDIX devices can communicate directly. Historically this was the method to link two PCs or two switches without a intermediary device. Modern Ethernet often handles this automatically with auto-MDI/MDIX, but the basic idea remains: the cable type is about matching transmit to receive between like devices. The other statements aren’t accurate: crossover cables aren’t the standard for all router connections, they don’t replace a switch, and connecting a computer directly to a wall port isn’t the typical use in standard setups.

Crossover cables are used to connect similar devices by flipping the transmit and receive pairs so the devices’ send and receive paths line up. In Ethernet, end devices like PCs and NICs are MDI, while switches (and other uplink devices) are MDIX. A crossover cable swaps the TX and RX lines so data from one MDI device is received by the other MDI device, or both MDIX devices can communicate directly. Historically this was the method to link two PCs or two switches without a intermediary device.

Modern Ethernet often handles this automatically with auto-MDI/MDIX, but the basic idea remains: the cable type is about matching transmit to receive between like devices. The other statements aren’t accurate: crossover cables aren’t the standard for all router connections, they don’t replace a switch, and connecting a computer directly to a wall port isn’t the typical use in standard setups.