Layer7

Layer7

In computer network programming, the application layer is an abstraction layer reserved for communications protocols and methods designed for process-to-process communications across an Internet Protocol (IP) computer network. Application layer protocols use the underlying transport layer protocols to establish host-to-host connections.

The Internet protocol suite (TCP/IP) and OSI model each specify a group of protocols and methods identified by the name application layer.

In the OSI model, the definition of its application layer is narrower in scope. It separates functionality above the transport layer at two additional levels, the session layer and the presentation layer. OSI specifies strict modular separation of functionality at these layers and provides protocol implementations for each layer.