The main functionality of application layer is getting data on to the network.
Application Layer Functionality and Protocols : -
- When we try to access information on a device, the data may not be physically stored on that device.
- If that is the case, a request must be made to the device where the data resides and we after that we can use the data.
- An application layer protocol defines how an application processes (clients and servers) , running on different end systems, pass messages to each other.
- In particular, an application layer protocol defines : - The type , The syntax The rule.
- Rules for determining when and how a process sends messages and responds to messages.