Which device operates at the data link layer of the OSI model?

The device that operates at the data link layer of the OSI model is a switch. Switches are responsible for directing data frames between devices on the same local area network (LAN) by using MAC addresses. They create a separate collision domain for each connected device, which helps in reducing network collisions and improves overall network efficiency.

Switches operate at Layer 2 of the OSI model, where they handle the MAC addressing and frame switching functions. They can also manage multiple data streams and ensure that data is sent to the appropriate device based on the MAC address contained within each frame.

While other devices such as bridges also function at the data link layer by connecting two or more network segments, the primary characteristic that distinguishes switches is their capability to intelligently direct traffic based on the MAC address table they maintain. This makes them more efficient in managing local traffic compared to a hub, which operates at the physical layer and simply broadcasts incoming frames to all ports without any intelligence or filtering. Similarly, routers function at the network layer, addressing IP packets, and are not specific to the data link layer functionality.