CompTIA Security Plus Mock Test Q1006

Symmetric encryption utilizes __________, while asymmetric encryption utilizes _________.

Public keys, one time
B. Shared keys, private keys
C. Private keys, session keys
D. Private keys, public keys

Correct Answer: D
Section: Cryptography

Symmetrical systems require the key to be private between the two parties. With asymmetric systems, each circuit has one key.
In more detail:
* Symmetric algorithms require both ends of an encrypted message to have the same key and processing algorithms. Symmetric algorithms generate a secret key that must be
protected. A symmetric key, sometimes referred to as a secret key or private key, is a key that isn’t disclosed to people who aren’t authorized to use the encryption system.
* Asymmetric algorithms use two keys to encrypt and decrypt data. These asymmetric keys are referred to as the public key and the private key. The sender uses the public key to
encrypt a message, and the receiver uses the private key to decrypt the message; what one key does, the other one undoes.

Incorrect Answers:
A: Symmetric encryption uses private keys, not public keys.
B: Symmetric encryption uses private keys, not shared keys.
C: Asymmetric encryption does not use session keys, it uses a public key to encrypt data.

Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis, 2014, pp. 251, 262