Layer 5 of the OSI model is the Session Layer, which establishes, manages, and terminates sessions between applications.
Following are some of the communication tasks performed at this layer:
- Establishing connections
- Maintaining connections
- Synchronizing communications
- Controlling dialogues
- Terminating connections
When you create a connection, you authenticate the user account at the sending and receiving computers. Connection creation also involves determining the type of communication that will take place and the protocols that will be used by the lower layers.
Data transfer and dialogue control are used to determine which computer is making requests and which computer is making responses. This also determines whether acknowledgments are required for data transmission.
A session is a series of related connection-oriented transmissions between network nodes. Another way to look at it is that a session is the interrelated communications between two or more presentation entities, which emphasizes that the Session layer provides services to the Presentation layer.
Tags: session layer, communication protocol layers, layers of communication protocol, communications protocols image, layer, Layer 5