Joe, a user, wants to protect sensitive information stored on his hard drive. He uses a program that
encrypted the whole hard drive. Once the hard drive is fully encrypted, he uses the same program to
create a hidden volume within the encrypted hard drive and stores the sensitive information within the
hidden volume. This is an example of which of the following? (Select TWO).

A.
Multi-pass encryption

B.
Transport encryption

C.
Plausible deniability

D.
Steganography

E.
Transitive encryption

F.
Trust models

Explanation:
Steganography is the process of concealing a file, message, image, or video within another file, message,
image, or video. In this case, it is a hidden volume within the encrypted hard drive.
In cryptography, deniable encryption may be used to describe steganographic techniques, where the very
existence of an encrypted file or message is deniable in the sense that an adversary cannot prove that an
encrypted message exists. This then provides you with plausible deniability.
Incorrect Answers:
A: Multi-pass encryption is not a valid encryption type.
B: Transport encryption is the process of encrypting data ready to be transmitted over an insecure
network.
E: Transitive comes across in trust models, it is not an encryption type.
F: A trust Model is collection of rules that informs application on how to decide the legitimacy of a Digital
Certificate.

Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis,
2014, pp. 136, 248
https://en.wikipedia.org/wiki/Plausible_deniability#Use_in_cryptography
https://technet.microsoft.com/en-us/library/cc962065.aspx