What are the primary responsibilities of session-layer protocols in managing dialog control and synchronization between communicating entities?

Session-layer protocols manage dialog control by coordinating the exchange of data between applications, ensuring that messages are delivered reliably and in the correct sequence. They handle synchronization by establishing checkpoints or synchronization points within the data stream, allowing communication to resume from a known state in case of failure or interruption. Additionally, they provide mechanisms for flow control and error recovery to maintain the integrity of the session.