Which layer does a switch operate in the OSI model?

A switch primarily operates in the Data Link Layer of the OSI model, which is the second layer. Its main function is to forward frames based on MAC addresses, facilitating communication between devices on the same local area network (LAN). By determining the appropriate destination for each data frame, the switch helps maintain efficient traffic flow within the network.

At the Data Link Layer, switches can also perform error checking and frame synchronization, which are crucial for maintaining the integrity of the data being transmitted. This capability distinguishes switches from devices that operate at the upper layers, which handle more complex tasks beyond just data transfer.

Operations at the Physical Layer involve the actual transmission and reception of raw bit streams over a physical medium, while the Network Layer is responsible for packet forwarding including routing through different networks. The Transport Layer is focused on end-to-end communication and reliability. Each of these layers serves a distinct purpose, but switch functionality aligns specifically with the role of the Data Link Layer in the OSI model.