WGU C839 Exam Study Questions and Answers
2023 – 2024 (Verified Answers)
1.Which encryption standard is approved by the National Security
Agency (NSA) for classified information ANS Advanced Encryption
Standard (AES
2.Which National Security Agency (NSA) encryption algorithms are
uneval- uated commercial cryptographic components ANS Type 4
3.Which method is used to verify the validity of a certificate ANS Online
Certifi- cate Status Protocol (OCSP)
4.What is used to protect an encryption key and deliver it quickly ANS
Digitally signed symmetrical key encryption sent via email
5.Why should a certificate authority (CA) assign an expiration date for
certificates it issues ANS A certificate with a short life span limits how
long data is vulnerable if the key is compromised
6.What is used as a virtual representation that identifies a person as an
entity by a trusted third party ANS Digital signature
7.Which attribute is common to stream ciphers ANS XORing pseudorandom bytes with plaintext
8.Which mode generates a pseudo-random stream of bytes and XORs
the plaintext while encrypting ANS Output feedback (OFB)
9.What is a common attribute of a streaming algorithm ANS It encrypts a
bit at a time.
10.What is required to decrypt data encrypted by a symmetric key ANS
An identical copy of the key
11.Which sender-identifying input must be provided when digitally
signing a message ANS Public key
12.What does m represent, assuming that the encryption function is