Which layer of the OSI model is responsible for establishing, managing, and terminating connections?

The session layer is responsible for establishing, managing, and terminating connections between applications. This layer plays a crucial role in maintaining sessions, which are ongoing connections between two communicating entities. It manages the dialogue between devices, ensuring that data is properly synchronized and that the communication sessions are controlled effectively.

This layer also handles the setup and teardown of connections, allowing applications to communicate without concern for the details of data transmission. By managing the session, it allows for more efficient data exchange, as it can control the flow of information and ensure that each session is maintained smoothly throughout its duration.

In contrast, the transport layer focuses on delivering messages between hosts reliably and ensuring complete data transfer, while the application layer provides network services directly to end-user applications. The network layer is responsible for data packet forwarding and routing through intermediary devices to reach the destination, but it does not manage connections or communication sessions. Thus, the session layer is the one specifically tasked with the management of connections.