Layer 7: Application. The Application Layer in the OSI model is the layer that is the “closest to the end user”. It receives information directly from users and displays incoming data to the user.

The application layer is layer 7 of 7 in the OSI model. For example, email, Web browsing and video streaming applications reside at layer 7. See TCP/IP and OSI model .

As a matter of fact, when I started writing this post I titled it “Layer 4 of the OSI Model – understanding the application layer,” and then I had to go back and correct myself.

More likely, it’s an application problem. ... Of the seven layers of the OSI Model, layers 5 and 6, the session and presentation layers, are the two least relevant layers for network engineers.

One of the most enduring models in networking is the famous seven-layer OSI model. X.25 roughly, but pretty accurately, is based on the first three layers. And it stopped there. Subsequently ...