Certified Ethical Hacker (CEH v10) — Question 170

User A is writing a sensitive email message to user B outside the local network. User A has chosen to use PKI to secure his message and ensure only user B can read the sensitive email. At what layer of the OSI layer does the encryption and decryption of the message take place?

Answer options

• A. Application
• B. Transport
• C. Session
• D. Presentation

Correct answer: D

Explanation

The correct answer is D, Presentation layer, as this layer is responsible for data translation and encryption/decryption. The Application layer (A) deals with end-user interface and application services, the Transport layer (B) manages data transfer and error recovery, and the Session layer (C) establishes and maintains sessions but does not handle encryption directly.