Question

Which of the following methods uses the concept that exponentiation is computationally inexpensive in the finite field?

(a) Diffie-HEllman key exchange

(b) RSA key exchange

(c) Arithmetic key exchange

(d) FSM method

I had been asked this question during an interview.

The above asked question is from Number Theory in chapter Number Theory and Cryptography of Discrete Mathematics

Answer 1

The correct choice is (a) Diffie-HEllman key exchange

Explanation: Exponentiation in the finite fields has its many applications in the public key cryptography system. Now, the Diffie–Hellman key exchange can have the concept that exponentiation is computationally inexpensive in the finite fields and the discrete logarithm which is the inverse of exponentiation, can be computationally expensive.