The reason it makes sense NOT to jump into deep packet inspection (or, as you ask, starting at L1), is that starting at an app layer you have a holistic view of *every* possible link in the chain. If ...

Layers 7 through 4 are geared more to the application than the lower layers, which are designed to move packets from one place to another no matter what they contain. This top layer defines the ...

According to the OSI Model, the session layer is where connections are established, managed, and torn down. For connection-oriented network protocols, understanding how the session layer works, and ...

For many in the communication industry, the open system interconnect (OSI) network model is a simply a stack. But, designers shouldn't be so quick to diminish the value that the OSI model provides to ...

The line between middleware and application software is blurred, which is why this chapter introduces both together. Middleware is software that has been abstracted out of the application layer for a ...

For many years, security monitoring relied on gathering data from layer 4 of the OSI model through such data types as NetFlow. Because layer 4 data dealt with the transport layer, it isn't the most ...