OSI Reference Model (OSI)

                              Layer 6              Presentation

                              Layer 5              Session

                              Layer 4              Transport

                              Layer 3              Network

                              Layer 2              Data link

                              Layer 1              Physical

(1)Application Layer

The top (seventh) layer of the OSI Reference Model is the application layer. It provides the user interface. Example of TCP/IP applications include telnet, FTP, HTTP, and SMTP. The seventh layer or topmost layer of the OSI Reference Model is the application layer. It provides the interface that a person user to interact with the application. The interface can be command-line interface CLI whereas a web browser uses a graphical interface. In the OSI Reference Model the application layer refers to applications that are network-aware. There are thousands of computer application across a network. This situation is changing rapidly however . Five years ago there was a distinct line between application that could and could not perform network functions. A good example of this was word processing programs like Microsoft word they were built to perform one process: word processing. Today however many applications Microsoft word for instance

Have  embedded objects that do not necessarily have to be on the same computer are telnet FTP web browsers and e-mail.