The Application Layer. This is the one located at the top portion of the model. This can provide all of the details for the user. This is in charge of providing interfaces, other protocols, and methods that can be used for communications. Take note that this is also used in the Internet Protocol Suite Model.
This will also allow you to see if there are some problems that are available that you did not see immediately when you checked the network. Take note that the other layers are meant to improve the process further. It has to go through different layers so that some details can be changed if they do not work.
To answer this query, let's put it into context. OSI helps isolate problems when you are troubleshooting networks. Of the different layers that an OSI comprises, the application layer comes first, then the presentation layer, then the session layer.
After this comes the transport layer, and this is where ftp and smtp reside. This is a kind of quality control; rogue elements should not be able to pass. There are three more layers after this transport layer.
Application layer-1.1 application layer: provides a means for the user to access information on the network through an application. this layer is the main interface for the user to interact with the application and therefore the network.the application layer is the osi layer closest to the end user, which means that both the osi application layer and the user interact directly with the software application. this layer interacts with software applications that implement a communicating component. such application programs fall outside the scope of the osi model. application layer functions typically include identifying communication partners, determining resource availability, and synchronizing communication. when identifying communication partners, the application layer determines the identity and availability of communication partners for an application with data to transmit. when determining resource availability, the application layer must decide whether sufficient network resources for the requested communication exist. in synchronizing communication, all communication between applications requires cooperation that is managed by the application layer.