The session layer is concerned with into host communication.
So this layer is involved in the establishment maintenance and termination of sessions between applications.
This allows two application processes on different machines to establish a session between them.
This acts as a coordinator of communication between the systems.
Examples of protocols that exist at this layer include remote procedure calls or pieces network file
system or NFL s an apple zone Information Protocol or zip.
This allows two application processes on different machines to establish use and terminate a connection
and that is called a session.
These perform functions that allow those processes to communicate to the network performing actions
providing security.
Name recognition logging and so forth.
A well-known example from the Microsoft world is net bios or network basic input output system.
And lastly point to point Tunneling Protocol or Pete PDP so various protocols at this layer ensure that
request and responses between applications can work properly over a session but between those end user
application processes.
So those were the top three layers of the OS model.