The application layer is described here in more detail.
The application layer is where we will begin our examination of the TCP/IP layers.
Table of Contents
Important Functions of the Application Layer
The application layer’s primary function is to make it possible for end users to access the Internet via a variety of apps. This entails:
- Writing information to the network in a manner that complies with the active protocol.
- Reading information from the user.
- Delivering to consumers programs that are helpful.
- Some programs additionally make sure that the data provided by the user is in the right format.
- Some programs additionally do error management and recovery.
The Postal System Analogy
- Imagine sending a box across the globe.
- The post system would presumably transfer it to a ship or an aircraft to go across the globe.
- To send it off, you would first take it to the post office. The application layer in networks transports the parcel to the post office, except that it carries messages to the transport layer!
Where It Is Present
The end systems are where the application layer is located. These end-systems may be any Internet-capable appliance, such as a Laptop, Mobile, etc.
Protocols for applications layers
The majority of people would contend that the real goal of the Internet is user applications. The Internet wouldn’t be what it is now if there were no helpful apps.
- Text-based network applications like e-mail served as the foundation for the growth of the Internet in the previous century.
- Then the app, the World Wide Web, came along and completely changed everything.
- The advent of instant messaging at the turn of the century revolutionized the way we communicate.
- Since then, voice over IP, WhatsApp calls, Skype video chat, and video streaming have all been developed (YouTube).
- Due to the global adoption of social media, companies and intricate human social networks have been built on top of these platforms.
These apps are all powered by protocols at the application layer. These common protocols allow client applications created by different manufacturers to communicate with server applications created by others.