Which OSI layer handles data representation, encryption, and compression for communication between applications?

• A. Application Layer (Layer 7)
• B. Presentation Layer (Layer 6)
• C. Session Layer (Layer 5)
• D. Transport Layer (Layer 4)

Answer: (B)

Data representation, encryption, and compression are handled by the Presentation Layer. This layer sits between the Session and Application layers and is responsible for making data from one system readable by another. It performs format translation and encoding conversion so that different systems can interpret the data consistently, and it applies encryption to protect the payload and compression to optimize bandwidth as data moves between applications. The Application Layer provides the actual software services, the Session Layer manages connections, and the Transport Layer focuses on reliable delivery; none of those mainly deal with formatting and securing the data as it travels, which is the role of the Presentation Layer.