|  |  | Overview

After data packets provided by the four lower layers travel through the transport layer, they are turned into sessions by the Layer 5 protocol or OSI session layer. This is done by implementing various control mechanisms. In this chapter, you will learn about these mechanisms. This includes accounting, conversation control, that is, determining who can talk when, and session parameter negotiation.

The chapter also describes how the session layer coordinates service requests and responses. This occurs when applications communicate between different hosts. You will learn about the processes which occur as data travels through the session layer. Included are, dialogue control and dialogue separation that enable applications to communicate between the source and destination.