Hubs works on Layer 1, Switches works on Layer 2, Router works on Layer 3. Then what is the difference between Layer 3 switch and router?

The Difference is that Layer-3 Switches can perform routing but can't connect different LANs through a WAN whereas they doesn't have WAN interfaces as Routers, so it is just to route packets between different VLANs within the same LAN, but Routers can have different WAN interfaces to be able to connect to remote LANs.

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