Episode 16: OSI Upper Layers and Data Encapsulation (Layers 5–7 and Encapsulation)

This episode explores the upper layers of the OSI model: Session, Presentation, and Application. These layers manage sessions between devices, format and translate data, and provide interfaces that allow end users and applications to interact with the network. While often grouped together for study purposes, each layer performs distinct functions that are tested on the exam. The discussion also introduces the concept of data encapsulation, explaining how information is wrapped with headers and trailers as it moves down the stack and unwrapped on the receiving end.

Practical examples are used to demonstrate these concepts, such as secure session establishment, data encryption and compression, and application-layer protocols like HTTP or SMTP. Understanding encapsulation is shown to be critical for interpreting packet headers and troubleshooting data flows, as errors can occur at multiple layers simultaneously. By connecting theory with practical analysis, this episode prepares you to recognize how upper-layer processes integrate with the entire networking model. Produced by BareMetalCyber.com, where you’ll find more cyber audio courses, books, and information to strengthen your certification path.