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WGU C839 INTRODUCTION TO CRYPTOGRAPHY EXAM
ACTUAL EXAM COMPLETE 200 QUESTIONS AND
CORRECT DETAILED ANSWERS JUST RELEASED
WGU C839 INTRODUCTION TO CRYPTOGRAPHY EXAM A
Which part of the public key infrastructure (PKI) defines how a credential is used? - ANSWER- Certificate policy (CP)
Which part of the public key infrastructure (PKI) is used to ensure that the format for a credential can be used by anyone on the internet? - ANSWER-Public Key Cryptography Standards (PKCS)
Which solution is used in a Layer 2 Tunneling Protocol (L2TP) virtual private network (VPN) to secure data in transmission? - ANSWER-Internet Protocol Security (IPsec)
Which network-based virtual private network (VPN) prevents unauthorized logins by preventing packet retransmission? - ANSWER-IP security (IPsec)
Which port does Secure Socket Tunneling Protocol (SSTP) use? - ANSWER-Port 443
What is a common problem with using pre-shared keys (PSKs)? - ANSWER-Secure key exchange
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2 What is a concern with storing long-term secrets on media or memory? - ANSWER-Integrity
Which cipher uses a series of ciphers based on a keyword? - ANSWER-Vigenère
Which substitution cipher system reverses the sequence of the alphabet? - ANSWER-Atbash
Which type of cipher converts a letter to a number, passes it through a mathematical function, and then converts it back to a letter? - ANSWER-Affine
Which technique solves polyalphabetic substitution ciphers by deducing the key length? - ANSWER-Kasiski's method
Which cryptanalysis technique examines ciphertext for recurring letter combinations? - ANSWER-Frequency analysis
Which cryptanalysis method involves a person being tricked into encrypting a set of known messages? - ANSWER-Chosen plaintext attack
Which technique does related-key cryptanalysis use to decipher a message? - ANSWER- Messages are encrypted using different secrets, and the analyst compares the messages to figure out how the algorithm works. 2 / 4
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Which type of cryptography is being used when the author uses secret inks? - ANSWER- Steganography
What is the hidden message in a steganographic communication? - ANSWER-Payload
How did the ATBASH cipher work? - ANSWER-By substituting each letter for the letter from the opposite end of the alphabet (i.e. A becomes Z, B becomes Y, etc.)
DES has a key space of what? - ANSWER-2 to the 56th power
Which of the following are valid key sizes for AES (choose three)? - ANSWER-128/192/256
Which of the following algorithms uses three different keys to encrypt the plain text? -
ANSWER-3DES
AES is what type of cipher? - 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? - ANSWER-Asymmetric 3 / 4
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Which of the following is an asymmetric cipher? - ANSWER-RSA
A cipher is defined as what - ANSWER-The algorithm(s) needed to encrypt and decrypt a message
AES is what type of system? - ANSWER-Symmetric systems
John is going to use RSA to encrypt a message to Joan. What key should he use? - ANSWER- Joan's public key
What advantage do symmetric algorithms have over asymmetric algorithms - ANSWER-They are faster
Which of the following is generally true about key sizes? - ANSWER-Larger key sizes increase security
A _____ is a function and is not reversible. - ANSWER-Hash
What are protocols for exchanging keys? - ANSWER-Diffie-Hellman (DH)/Menezes-Qu-Vanstone (MQV)/Elliptic-curve Diffie-Hellman (ECDH)
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