Question 73

D: Transport

The Transport layer of the OSI model is responsible for end-to-end encryption, ensuring that data is securely transmitted between devices across a network.

A) Presentation

The Presentation layer primarily focuses on data translation, formatting, and encryption, but it does not handle end-to-end encryption. Its role is to prepare data for the application layer, making it incorrect for this question.

B) Application

The Application layer serves as the interface for user applications and is responsible for application-level functions, but it does not manage end-to-end encryption. Although it may utilize encryption protocols, it does not directly provide encryption services itself.

C) Session

The Session layer is responsible for establishing, managing, and terminating sessions between applications. While it may support some aspects of secure communication, it does not provide the end-to-end encryption that is characteristic of the Transport layer.

D) Transport

The Transport layer is indeed responsible for end-to-end encryption, as it manages the delivery of messages across a network and can utilize encryption protocols like TLS to protect data during transmission.

Conclusion

The Transport layer is essential for ensuring secure, encrypted communication between devices, making it the correct choice. Other layers play supportive or preparatory roles but do not directly handle the encryption of data between endpoints. Thus, D is the definitive answer.