What property does Diffie-Hellman provide?

• A. Confidentiality of the key exchange
• B. Digital signatures
• C. Data integrity
• D. Public key encryption

Answer: (A)

Diffie-Hellman is about establishing a secret key over an insecure channel. By exchanging publicly visible values based on private exponents, two parties can derive a shared secret that an eavesdropper cannot compute from the public data alone. That shared secret can then be used as a symmetric key to protect future communication, ensuring the confidentiality of the key exchange itself. It does not provide digital signatures, data integrity by itself, or direct encryption of messages with a recipient’s public key. It also needs authentication to prevent man-in-the-middle attacks.