Negotiating a shared encryption key involves a process where two parties agree on a secret key over
an insecure channel without directly transmitting it. This is distinct from encryption or hashing
algorithms, which serve different purposes.
Why C is correct: The Diffie-Hellman (DH) algorithm is a key exchange protocol that enables two
parties to establish a shared secret key using mathematical operations (e.g., modular
exponentiation). It’s widely used in protocols like TLS and IPsec, as noted in CNSP for secure key
negotiation.
Why other options are incorrect:
A: Triple-DES is a symmetric encryption algorithm for data encryption, not key negotiation.
B: SHA1 is a hash function for integrity, not key exchange.
D: AES is a symmetric encryption algorithm, not a key exchange mechanism.
Reference: CNSP "Cryptographic Protocols" (Section on Key Exchange) describes Diffie-Hellman as
the standard for shared key negotiation, contrasting it with encryption algorithms.
