Which device connects multiple LAN segments and separates collision domains by filtering traffic at the data link layer?

Which device connects multiple LAN segments and separates collision domains by filtering traffic at the data link layer?

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

Answer: (C)

The key idea here is a device that connects multiple LAN segments and reduces collisions by making forwarding decisions at the data link layer. A bridge fits this role because it operates at Layer 2 and learns which devices are reachable on each segment via MAC addresses. By examining the destination MAC, it forwards frames only to the appropriate segment, effectively separating collision domains between the connected LAN segments and keeping unnecessary traffic from crossing into other parts of the network. A hub cannot do this; it simply repeats traffic to all ports, so all devices share a single collision domain. A router operates at the network layer and links different networks or subnets, not just LAN segments in the same broadcast domain. A switch does perform similar filtering at Layer 2 and can separate collision domains on each port, but the description aligns with the traditional role of a bridge—connecting LAN segments and filtering traffic to manage collisions.

The key idea here is a device that connects multiple LAN segments and reduces collisions by making forwarding decisions at the data link layer. A bridge fits this role because it operates at Layer 2 and learns which devices are reachable on each segment via MAC addresses. By examining the destination MAC, it forwards frames only to the appropriate segment, effectively separating collision domains between the connected LAN segments and keeping unnecessary traffic from crossing into other parts of the network.

A hub cannot do this; it simply repeats traffic to all ports, so all devices share a single collision domain. A router operates at the network layer and links different networks or subnets, not just LAN segments in the same broadcast domain. A switch does perform similar filtering at Layer 2 and can separate collision domains on each port, but the description aligns with the traditional role of a bridge—connecting LAN segments and filtering traffic to manage collisions.