Describe the important features of application layer.

The features of the application layer are as follows.

1. Efficient User Interface Design is explained below:

Application layer, the top layer of the OSI model serves as Interface between the user and application and also between the user and the network. It gives the user, a way of accessing information present on the network through an application. Since the application layer is closest to the end user, both the user and the application layer can interact directly with the application.

2.   Identification of Communicating Parties is explained below:

Application layer defines the way ‘how’ an application running on one system communicates with an application on another system.  In addition to this, the layer also determines ‘who’ the communicating partners are and whether they are ready for communication or not (that is their identity and availability) whenever there is an application which has the data to transmit.

3.   Determination of Resource Availability is explained below:

For the communication to be successful a number of resources are needed. So, whenever the communication request is made, the application layer checks whether the existing network resources  are  sufficient  for  handling  the  communication  request or not.  Thus, it determines the availability of the resources.

4.   Synchronization of communication is explained below:

The application layer is responsible for checking either the two communicating parties are synchronized or not. It performs this by ensuring that both the parties employ the similar network protocols and that the communication is done in the cooperative manner.

5. Implementation of Protocols is explained below:

The application layer implements the various protocols like Telnet, FTP (File Transfer Protocol), HTTP (Hyper Text Transfer Protocol), SMTP (Simple Mail Transfer Protocol) and many more.  Among which the most broadly used one is HTTP. This protocol is basis for the World Wide Web. When the users require accessing some web pages of the website, then they specify name of the page in the URL and then send it to the servers using the browser. This request is sent as the HTTP request and response is also sent back to the user using HTTP protocol.