Straight-through Ethernet cables are commonly used to connect which pair of devices?

Straight-through Ethernet cables are commonly used to connect which pair of devices?

• A. PC to PC
• B. Router to modem
• C. Switch to switch
• D. Computer to switch

Answer: (D)

Straight-through Ethernet cables are used to connect devices of different types, so the signal from a host’s network interface card (the computer) goes to a network device that expects to talk to hosts (a switch). This alignment—host to switch—has been the standard way to build a LAN, because the host (MDI) pairs with the switch (MDI‑X) so TX on one side matches RX on the other. That’s why the common, and best, example is computer to switch. The other pairings are typically associated with crossover cables in older setups (like PC to PC or switch to switch), where like devices needed TX to TX and RX to RX to communicate. Modern NICs and switches often auto-sense, reducing the impact of cable type, but the fundamental idea remains: straight-through connects different device types, with computer to switch being the classic illustration.

Straight-through Ethernet cables are used to connect devices of different types, so the signal from a host’s network interface card (the computer) goes to a network device that expects to talk to hosts (a switch). This alignment—host to switch—has been the standard way to build a LAN, because the host (MDI) pairs with the switch (MDI‑X) so TX on one side matches RX on the other. That’s why the common, and best, example is computer to switch.

The other pairings are typically associated with crossover cables in older setups (like PC to PC or switch to switch), where like devices needed TX to TX and RX to RX to communicate. Modern NICs and switches often auto-sense, reducing the impact of cable type, but the fundamental idea remains: straight-through connects different device types, with computer to switch being the classic illustration.