INTRODUCTION TO CRYPTOGRAPHY OA EXAM
QUESTIONS AND CORRECT ANSWERS | LATEST VERSIONS
(VERSION A & B) 2026/2027 | GUARANTEED A+.
What is a concern with storing long-term secrets on media or memory?
- CORRECT-ANSWER-Integrity
Which cipher uses a series of ciphers based on a keyword? - CORRECT-
ANSWER-Vigenère
Which type of cipher converts a letter to a number, passes it through a
mathematical function, and then converts it back to a letter? -
CORRECT-ANSWER-Affine
Which technique solves polyalphabetic substitution ciphers by deducing
the key length? - CORRECT-ANSWER-Kasiski's method
,Which cryptanalysis technique examines ciphertext for recurring letter
combinations? - CORRECT-ANSWER-Frequency analysis
Which substitution cipher system reverses the sequence of the alphabet?
- CORRECT-ANSWER-Atbash
Which cryptanalysis method involves a person being tricked into
encrypting a set of known messages? - CORRECT-ANSWER-Chosen
plaintext attack
Which technique does related-key cryptanalysis use to decipher a
message? - CORRECT-ANSWER-Messages are encrypted using
different secrets, and the analyst compares the messages to figure out
how the algorithm works.
Which type of cryptography is being used when the author uses secret
inks? - CORRECT-ANSWER-Steganography
What is the hidden message in a steganographic communication? -
CORRECT-ANSWER-Payload
, How did the ATBASH cipher work? - CORRECT-ANSWER-By
substituting each letter for the letter from the opposite end of the
alphabet (i.e. A becomes Z, B becomes Y, etc.)
Which of the following algorithms uses three different keys to encrypt
the plain text? - CORRECT-ANSWER-3DES
AES is what type of cipher? - CORRECT-ANSWER-Block Cipher
Which of the following is a type of encryption that has two different
keys. One key can encrypt the message and the other key can only
decrypt it? - CORRECT-ANSWER-Asymmetric
Which of the following is an asymmetric cipher? - CORRECT-
ANSWERRSA