At which layer of the OSI model are frames handled?

Frames are handled at the Data Link layer of the OSI model. This layer is responsible for node-to-node data transfer and ensures that data is packaged into frames with appropriate headers and footers. These frames include control information for error detection, frame synchronization, and other protocols necessary for data transmission over a physical medium.

The Data Link layer plays a critical role in establishing connections between devices on the same network, managing how data is placed and received from the physical medium. It deals with the physical addressing and the way data packets are actually transferred over the physical connection, which is essential for maintaining the integrity and reliability of data communications.

In contrast, the other layers serve different functions: the Network layer is responsible for logical addressing and routing, the Transport layer provides end-to-end communication and error recovery, and the Application layer focuses on user interface and application-specific functions. Thus, while all these layers contribute to the overall data transmission process, frames are specifically managed at the Data Link layer.