What device functions as both a router and a switch?

A Layer 3 switch functions as both a router and a switch by combining the capabilities of both devices. Specifically, it operates at the Network Layer of the OSI model, enabling it to perform routing functions, such as managing IP addresses and making forwarding decisions based on the Layer 3 header information.

In addition to routing, a Layer 3 switch can also switch packets at high speeds, similar to a traditional Layer 2 switch. This hybrid functionality allows for efficient traffic management within a local area network (LAN), where it can facilitate communication between different VLANs (Virtual Local Area Networks) and improve overall network performance.

This integration of routing capabilities with traditional switching provides a significant advantage in network design by reducing the need for separate devices, minimizing latency, and streamlining the architecture. Thus, a Layer 3 switch is essential in environments where inter-VLAN routing and high-performance switching are necessary.