MSIS 4123 Quiz 7 Questions with Correct Answers Latest Update 2025/2026
After encrypting a plaintext file and saving its ciphertext in a new file, what should the file
encryption program do next? Select the safest alternative. - Answers The program writes zeroes
over every data block in the plaintext file.
What is/are the input(s) for a decryption procedure? Select all that apply. - Answers Ciphertext
A key
An encryption algorithm that uses the same key for both encryption and decryption is: - Answers
symmetric.
Encryption protects information by presenting which of the following? - Answers Key
An algorithm is a type of: - Answers procedure
The type of cipher that rearranges the text of a message is called: - Answers transposition.
True or False? Microsoft's built in encryption protects the user's file against a CryptoLocker
ransomware. - Answers False
True or False? The Advanced Encryption Standard (AES) is stronger than the Data Encryption
Standard (DES). - Answers True
The steps below describe how to use an encryption program. Arrange the steps in their proper
order. - Answers Step 1.
Select the file to encrypt.
Step 2.
Provide the key to encrypt the file.
Step 3.
The program encrypts the file and saves the encrypted copy.
Step 4.
The program erases the plaintext version of the file and erases the key from RAM.
Encryption transfers readable ____________ into unreadable _____________ using secret
information called a _______. - Answers plaintext; ciphertext; key
True or False? Microsoft Windows 10 Professional edition includes an encryption system called
BitLocker. - Answers True
_________________is a cipher that changes the order in which the messages symbols appear. -
, Answers Transposition cipher
_________________is a cipher that changes the symbols in the message, while retaining their
order in the message. - Answers Substitution cipher
Which of the following are true about a one-time pad? Select all that apply. - Answers Is
theoretically impossible to crack
Uses a random stream of bits for its key stream
The Enigma was used by the _________ in World War II. - Answers Germans
Why do protocols like IKE and SSL exchange nonces as part of their key creation/exchange
protocol? Select all that apply. - Answers no (The nonces provide additional secret randomness
to make the generated keys harder to guess. )
yes (New nonce values should make it impossible for an attacker to replay a previous set of
messages and force the connection to reuse a previous key. )
True or False? The two primary types of symmetric algorithms are public key cipher and private
key cipher. - Answers false
True or False? An encryption application program, from a user's point of view, protects a file
with a memorized password. - Answers True
_____________ is a message before its contents are hidden using a code or cipher. - Answers
Plaintext
A Caesar cipher encrypts texts by shifting letters three places, so that A becomes D. Decode
this phrase: zhoo grqh. - Answers well done
True or False? After encrypting a plaintext file, it should actively erase the plaintext file's content
and save the encryption. - Answers True
_________________is a cipher that uses the same key for both encryption and decryption. -
Answers Symmetric cipher
Which cipher replaces A with D and B with E? - Answers Caesar
In cryptography, key is _________________________________. - Answers the changeable part of the
encryption process that remains secret
Which of the following is a stream cipher algorithm? - Answers RC4 (Rivest's cipher 4)
Which of the following is a block cipher algorithm? - Answers All of the others
Bob and Kevin are both using symmetric crypto to exchange sensitive information with other
people. Although Bob and Kevin sometimes exchange sensitive information using a symmetric
After encrypting a plaintext file and saving its ciphertext in a new file, what should the file
encryption program do next? Select the safest alternative. - Answers The program writes zeroes
over every data block in the plaintext file.
What is/are the input(s) for a decryption procedure? Select all that apply. - Answers Ciphertext
A key
An encryption algorithm that uses the same key for both encryption and decryption is: - Answers
symmetric.
Encryption protects information by presenting which of the following? - Answers Key
An algorithm is a type of: - Answers procedure
The type of cipher that rearranges the text of a message is called: - Answers transposition.
True or False? Microsoft's built in encryption protects the user's file against a CryptoLocker
ransomware. - Answers False
True or False? The Advanced Encryption Standard (AES) is stronger than the Data Encryption
Standard (DES). - Answers True
The steps below describe how to use an encryption program. Arrange the steps in their proper
order. - Answers Step 1.
Select the file to encrypt.
Step 2.
Provide the key to encrypt the file.
Step 3.
The program encrypts the file and saves the encrypted copy.
Step 4.
The program erases the plaintext version of the file and erases the key from RAM.
Encryption transfers readable ____________ into unreadable _____________ using secret
information called a _______. - Answers plaintext; ciphertext; key
True or False? Microsoft Windows 10 Professional edition includes an encryption system called
BitLocker. - Answers True
_________________is a cipher that changes the order in which the messages symbols appear. -
, Answers Transposition cipher
_________________is a cipher that changes the symbols in the message, while retaining their
order in the message. - Answers Substitution cipher
Which of the following are true about a one-time pad? Select all that apply. - Answers Is
theoretically impossible to crack
Uses a random stream of bits for its key stream
The Enigma was used by the _________ in World War II. - Answers Germans
Why do protocols like IKE and SSL exchange nonces as part of their key creation/exchange
protocol? Select all that apply. - Answers no (The nonces provide additional secret randomness
to make the generated keys harder to guess. )
yes (New nonce values should make it impossible for an attacker to replay a previous set of
messages and force the connection to reuse a previous key. )
True or False? The two primary types of symmetric algorithms are public key cipher and private
key cipher. - Answers false
True or False? An encryption application program, from a user's point of view, protects a file
with a memorized password. - Answers True
_____________ is a message before its contents are hidden using a code or cipher. - Answers
Plaintext
A Caesar cipher encrypts texts by shifting letters three places, so that A becomes D. Decode
this phrase: zhoo grqh. - Answers well done
True or False? After encrypting a plaintext file, it should actively erase the plaintext file's content
and save the encryption. - Answers True
_________________is a cipher that uses the same key for both encryption and decryption. -
Answers Symmetric cipher
Which cipher replaces A with D and B with E? - Answers Caesar
In cryptography, key is _________________________________. - Answers the changeable part of the
encryption process that remains secret
Which of the following is a stream cipher algorithm? - Answers RC4 (Rivest's cipher 4)
Which of the following is a block cipher algorithm? - Answers All of the others
Bob and Kevin are both using symmetric crypto to exchange sensitive information with other
people. Although Bob and Kevin sometimes exchange sensitive information using a symmetric
