Which OSI layer does a switch belong to?

A switch operates primarily at Layer 2 of the OSI model, which is the Data Link layer. This layer is responsible for node-to-node data transfer, framing, and addressing. Switches use MAC (Media Access Control) addresses to forward data to the appropriate devices on a local area network (LAN). By working at this layer, a switch can efficiently filter and forward packets based on these addresses, ensuring that data is sent directly to its destination without unnecessary broadcasting, which is a key function of a switch in managing network traffic.

In contrast, Layer 1 (Physical) deals with the physical connection between devices and the transmission of raw bits over a physical medium, but it does not involve data addressing or formatting. Layer 3 (Network) is responsible for routing packets between different networks using IP addresses, and Layer 4 (Transport) manages end-to-end communication and data flow control, ensuring complete data transfer and integrity. These layers do not perform the specific functions related to data framing and MAC addressing that are essential aspects of a switch's operation within a network.