Which of the following type of cryptography is used when both parties use the same key to communicate
securely with each other?

A.
Symmetric Key Cryptography

B.
PKI – Public Key Infrastructure

C.
Diffie-Hellman

D.
DSS – Digital Signature Standard

Explanation:
A single secret key is used between entities when using symmetric key cryptography.
Incorrect Answers:
B: Public Key Infrastructure (PKI) is an ISO authentication framework that makes use of public key
cryptography and the X.509 standard.
C: Diffie-Hellman is the first asymmetric key agreement algorithm.
D: The Digital Signature Standard (DSS) refers to the U.S. standard that defines the approved algorithms to be
used for digital signatures for government authentication activities.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, 2013, pp. 782, 812, 833