This layer manages computer-to-computer dialogues (connections). The layer creates, manages and closes connections between local and remote applications. Layer 5 supports full-duplex, half-duplex and simplex operation and check-pointing, adjournment, termination and restart processes.
Layer 5, the session layer, provides various functions, including recording the number of bytes recognized by each end of the session from the other end of the session. This layer is responsible for seamlessly closing sessions, as well as session check-pointing and recovery. In application contexts that leverage remote procedure calls, the session layer is frequently built explicitly. This session layer enables device-based apps to start, manage and end a network-based dialogue.