Which networking device connects devices on a LAN and uses MAC addresses to forward data to the correct destination?

• A. Router
• B. Hub
• C. Ethernet Switch
• D. Bridge

Answer: (C)

When devices on a local area network communicate, a device that uses hardware addresses (MAC addresses) to forward frames to the correct destination is the Ethernet switch. It operates at Layer 2, learning the MAC addresses of devices by inspecting the source address of each frame it receives and building a table that maps each MAC address to the port it came in on. With this MAC address table, the switch forwards an incoming frame only to the specific port where the destination device is reachable, rather than sending it to every connected device.

If the destination MAC isn’t yet in the table, the switch floods the frame to all ports except the source until it learns where the destination is, then uses the precise port for subsequent frames. This approach creates separate collision domains for each port, increasing network efficiency and reducing unnecessary traffic.

A hub, by contrast, merely repeats incoming signals to all ports, so it doesn’t use MAC addresses to direct traffic and all devices share a single collision domain. A router routes packets between different networks using IP addresses (Layer 3), not within a single LAN. A bridge also uses MAC addresses to forward frames at Layer 2, but in typical LAN setups the device described for connecting multiple devices on a LAN and handling MAC-based forwarding is an Ethernet switch.