Layer 3 device

Layer 3 device

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

Answer: (B)

Layer 3 is the Network layer, which handles routing IP packets between different networks. A router operates at this layer, examining the IP header, using a routing table (and possibly routing protocols) to decide the best path, and forwarding the packet toward its destination across network boundaries. That inter-network routing is exactly what defines a Layer 3 device. In contrast, bridges and switches work primarily at Layer 2, forwarding frames based on MAC addresses within the same local network. Hubs are even simpler, just repeating signals without any addressing awareness. So the device that fulfills the Layer 3 routing role is the router.

Layer 3 is the Network layer, which handles routing IP packets between different networks. A router operates at this layer, examining the IP header, using a routing table (and possibly routing protocols) to decide the best path, and forwarding the packet toward its destination across network boundaries. That inter-network routing is exactly what defines a Layer 3 device.

In contrast, bridges and switches work primarily at Layer 2, forwarding frames based on MAC addresses within the same local network. Hubs are even simpler, just repeating signals without any addressing awareness. So the device that fulfills the Layer 3 routing role is the router.