Which layer of the OSI model does the MAC address operate at?

The MAC address operates at the Data Link layer of the OSI model. This layer is responsible for the physical addressing of devices on a local network. The MAC (Media Access Control) address is a hardware identifier that uniquely identifies each device on a local network segment and is used for communication between devices in the same local area network (LAN).

At this layer, protocols and standards define how data is formatted for transmission, how access to the physical medium is controlled, and how devices communicate over the local network. The Data Link layer ensures that the data packets are delivered to the correct device using the MAC address, which is vital for local network communication.

In contrast, the Application layer deals with the end-user applications and network services, providing network services directly to the user. The Session layer manages sessions between users, and the Network layer handles logical addressing and routing of packets across multiple networks but does not deal with hardware-specific addressing like that of the MAC.