Question

Your organization has decided to implement the Diffie-Hellman asymmetric algorithm. Which statement is true of this algorithm's key exchange?

A) Authorized users exchange public keys over a secure medium.
B) Unauthorized users exchange public keys over a nonsecure medium.
C) Authorized users exchange secret keys over a nonsecure medium.
D) Authorized users need not exchange secret keys.

Answer 1

The true statement about the Diffie-Hellman algorithm's key exchange is that authorized users exchange public keys over a nonsecure medium and then use these keys to generate a shared secret key for encryption.

Step-by-step explanation:

The Diffie-Hellman algorithm is used for securely exchanging cryptographic keys over a public channel. The correct statement in the context of the Diffie-Hellman algorithm is that authorized users exchange public keys over a nonsecure medium. This process allows two parties to generate a shared secret key without the need to exchange it directly. The shared secret key can then be used to encrypt subsequent communications using a symmetric key cipher.

A unique aspect of Diffie-Hellman is that it is an asymmetric algorithm used for creating a shared secret, rather than for encryption or digital signatures. Both parties exchange public components and use their private secrets to compute the shared secret offline. This is based on the mathematical principle that, while it's easy to compute exponential operations, it is hard to do the inverse (logarithm) in modular arithmetic, which underpins the security of Diffie-Hellman.