|  |  | Overview

Now that you have seen what happens to data packets as they travel the presentation layer, it's time to look at the last layer in which data packets travel through before reaching their final destination. The last layer or Layer 7 of the OSI model is referred to as the application layer. The application layer is the closest to you as an end-user, when you are interacting with software applications such as sending and receiving e-mail over a network. You will see how the application layer deals with data packets from client-server applications, domain name services, and network applications by examining the following:

- Client-Server
- Redirectors
- Domain Name System
- E-mail
- Telnet
- FTP
- HTTP