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WGU C839 INTRODUCTION TO CRYPTOGRAPHY EXAM
LATEST 2024-2025 ACTUAL EXAM A, B & PRACTICE
EXAM COMPLETE 500 QUESTIONS AND VERIFIED
CORRECT ANSWERS ALREADY GRADED A+
WGU C839 INTRODUCTION TO CRYPTOGRAPHY EXAM A
With _____, the message is divided into blocks and each block is encrypted separately. This is the most basic mode for symmetric encryption.
A Electronic codebook (ECB) B Cipher-block chaining (CBC) C Cipher feedback (CFB) D Output feedback (OFB) - ANSWER-A
Which of the following is an example of an unbalanced Feistel?
A 3DES
B Skipjack C Twofish
D AES - ANSWER-B
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2 This process is done by having each block of plaintext is XORed with the previous ciphertext block before being encrypted.
A Output feedback (OFB) B Cipher-block chaining (CBC) C Electronic codebook (ECB) D Cipher feedback (CFB) - ANSWER-B
The process wherein the ciphertext block is encrypted then the ciphertext produced is XOR'd back with the plaintext to produce the current ciphertext block is called what?
A Output feedback (OFB) B Cipher-block chaining (CBC) C Cipher feedback (CFB) D Electronic codebook (ECB) - ANSWER-C
This is a method for turning a block cipher into a stream cipher by generating a keystream block, which are then XORed with the plaintext blocks to get the ciphertext.
A Cipher feedback (CFB) 2 / 4
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3 B Electronic codebook (ECB) C Output feedback (OFB) D Cipher-block chaining (CBC) - ANSWER-C
Which of the following modes can be used to turn a block cipher into a stream cipher?
A Propagating cipher-block chaining (PCBC) and Electronic codebook (ECB)
B Counter Mode (CTR) and Propagating cipher-block chaining (PCBC)
C Electronic codebook (ECB) and Output feedback (OFB)
D Output feedback (OFB) and Counter Mode (CTR) - ANSWER-D
A fixed-size pseudorandom number that is fed into a symmetric cipher to increase randomness is called what?
A IV B Key 3 / 4
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4 C Chain D Salt - ANSWER-A
A number that is used only one time then discarded is called what?
A Nonce B Chain C Salt
D IV - ANSWER-A
Which of the following is a stream cipher that uses variable length key from 1 to 256 bytes?
A RC4 B AES C DESx
D DES - ANSWER-A
This algorithm was published by the German engineering firm Seimans in 1993. It is a software based stream cipher using Lagged Fibonacci generator along with a concept borrowed from the shrinking generator ciphers.
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