What is the difference between a switch and a bridge?

• A. A bridge is a multi-port Layer 2 device; a switch connects two network segments and can learn MAC addresses similarly
• B. A switch is a multi-port Layer 2 device; a bridge connects two network segments and can learn MAC addresses similarly
• C. A bridge operates at Layer 3 to route between networks
• D. A switch forwards frames only based on IP addresses

Answer: (B)

At the Data Link layer, both devices forward frames using MAC addresses and build a MAC address table to send frames only to the correct port. The difference is how many ports they typically have and how they’re used. A switch is a multi-port Layer 2 device, designed to connect many devices and forward frames to the specific port of the destination MAC. A bridge, on the other hand, traditionally connects two network segments and also learns MAC addresses to forward frames between those segments. So the switch extends the bridge’s concept to more ports while performing the same MAC-learning and forwarding behavior. The other options mix up Layer 2 with Layer 3 roles: routing between networks is a router’s job, and forwarding based on IP addresses is a Layer 3 function, not how a switch operates.