Question 1

What are three commonly used functions used by encryption algorithms?

Accepted Answer

The answer of What are three commonly used functions used...

Question 2

An attacker may obtain duplicate texts, one in ciphertext and one in plaintext, which enable the individual to reverse-engineer the encryption algorithm in a ____ attack.

Accepted Answer

This type of attack is called a known-plaintext attack, where the attacker has access to both the ciphertext and plaintext of the same message. By analyzing the pairs of plaintext and ciphertext, the attacker may be able to deduce the encryption algorithm used.

Question 3

Match each item with a statement below.
-The transformation of the individual components (characters, bytes, or bits) of an unencrypted message into encrypted components.

Accepted Answer

The answer of Match each item with a statement below.
-The...

Question 4

Match each item with a statement below.
-The set of transformations necessary to convert an unencrypted message into an encrypted message.

Accepted Answer

A cryptosystem is the set of transformations necessary to convert an unencrypted message into an encrypted message.

Answer: A
 A cipher is a specific algorithm or method of encryption.

Answer: C
 To encipher means to encrypt a message.

Answer: E
 Ciphertext is the encrypted message.

Answer: G
 To decipher means to decrypt a message.

Answer: H
 An algorithm is a set of instructions or rules that dictate how a cryptosystem or cipher works.

Answer: I
 A cryptovariable is a variable or value used in a cryptosystem that can be changed to affect the encryption and ensure security.

Note: B and F are not directly related to the given statements.

Question 5

In ____________________ cipher conversion, the bit stream is subjected to a Boolean XOR function against some other data stream, typically a key stream.

Accepted Answer

The answer of In ____________________ cipher conversion, the bit stream...

Question 6

In e-commerce, some cryptographic tools can be used to assure that parties to the transaction are authentic, so that they cannot later deny having participated in a transaction, a feature often called ____________________.

Accepted Answer

The answer of In e-commerce, some cryptographic tools can be...

Question 7

Session ____________________ are attacks involving a communication session that has already been established between a server and a client.

Accepted Answer

The answer of Session ____________________ are attacks involving a communication...

Question 8

PKI systems are based on public key cryptosystems and include digital certificates and certificate ____________________.

Accepted Answer

The answer of PKI systems are based on public key...

Question 9

Match each item with a statement below.
-The amount of effort (usually expressed in units of time) required to perform cryptanalysis on an encoded message.

Accepted Answer

Work factor refers to the amount of effort required to perform cryptanalysis on an encoded message.

Answer: A
 A cipher is a method for encrypting or decrypting a message.

Answer: B
 Keyspace refers to the total number of possible keys in a cryptographic system.

Answer: C
 Encipher means to convert plaintext into ciphertext.

Answer: D
 A cryptosystem refers to a set of cryptographic algorithms and protocols used to secure communications.

Answer: E
 Ciphertext refers to the encrypted form of a message.

Answer: G
 Decipher means to convert ciphertext into plaintext.

Answer: H
 An algorithm is a set of instructions used to perform a specific task.

Answer: I
 A cryptovariable is a variable used in a cryptographic system, such as a key or password.

Question 10

Match each item with a statement below.
-To decrypt or convert ciphertext to plaintext.

Accepted Answer

Decipher means to convert ciphertext back to plaintext.

Answer: A 
 Cipher refers to a specific method or technique used to encrypt plaintext.

Answer: G 
 Encipher means to convert plaintext to ciphertext.

Answer: D 
 Cryptosystem refers to the entire system used for encryption and decryption, including the algorithms and keys.

Answer: E 
 Ciphertext refers to the encrypted form of plaintext.

Answer: F 
 Work factor refers to the amount of time and resources required to break a particular encryption.

Answer: G 
 Decipher means to convert ciphertext back to plaintext.

Answer: H 
 Algorithm refers to the specific set of instructions used for encryption and decryption.

Answer: I 
 Cryptovariable refers to the key or set of keys used in a particular encryption algorithm.

The best choices are: 
Answer: GADGHI 
 The answer includes one choice each for decrypting (G), encrypting (A), the entire encryption system (D), ciphertext (E), work factor (F), deciphering (G), algorithm (H), and cryptovariable (I).

Question 11

____ attacks can be successful when the ciphertext consists of relatively few characters.

Accepted Answer

Dictionary attacks are typically used to crack passwords by trying a large number of words from a pre-built list. This attack can be successful when the ciphertext is a simple substitution cipher and the message consists of a small number of characters. If the message is long or the ciphertext is encrypted using a more complex encryption algorithm, dictionary attacks become less effective.

Question 12

____ attacks are collections of brute-force methods that attempt to deduce statistical relationships between the structure of the unknown key and the ciphertext that is the output of the cryptosystem.

Accepted Answer

Correlation attacks are specifically designed to identify statistical relationships between the key and ciphertext. This can involve analyzing a large number of ciphertexts in order to search for patterns that may indicate weaknesses in the encryption algorithm. Man-in-the-middle, dictionary, and timing attacks are all different types of attacks that do not necessarily rely on statistical analysis.

Question 13

Define encryption.

Accepted Answer

The answer of Define encryption....

Question 14

Match each item with a statement below.
-To encrypt or convert plaintext to ciphertext.

Accepted Answer

Encipher means to encrypt or convert plaintext to ciphertext.

Answer: A
 Cipher is a method of encryption or a specific encryption algorithm.

Answer: E
 Ciphertext refers to the encrypted message produced by the encryption algorithm.

Answer: D
 Cryptosystem refers to the set of rules and protocols for encryption and decryption of messages.

Answer: H
 Algorithm refers to the step-by-step process used to encrypt or decrypt a message.

Answer: F
 Work factor refers to the amount of time, effort, and resources required to crack a particular encryption algorithm.

Answer: G
 Decipher means to decrypt or convert ciphertext back to plaintext.

Answer: B
 Keyspace refers to the total number of possible keys that can be used in an encryption algorithm.

Answer: I
 Cryptovariable refers to a variable used in the encryption algorithm to produce the ciphertext.

Question 15

Match each item with a statement below.
-The encrypted or encoded message resulting from an encryption.

Accepted Answer

Ciphertext is the encrypted or encoded message resulting from an encryption.

Answer: A
 Cipher refers to a specific encryption method or technique used in cryptography.

Answer: C
 Encipher means to encrypt a message using a cipher or encryption algorithm.

Answer: D
 Cryptosystem refers to the combination of all the components used in cryptography to ensure secure communication.

Answer: G
 Decipher means to decrypt a message that has been encrypted, returning it to its original plaintext form.

Answer: H
 Algorithm is a series of steps or instructions used in cryptography to transform plaintext into ciphertext or vice versa.

Answer: I
 Cryptovariable refers to the secret key or password used in cryptography to encrypt and decrypt messages.

The choices B and F are not matched with any of the statements provided.

Question 16

____ is a Kerberos service that generates and issues session keys.

Accepted Answer

The Key Distribution Center (KDC) is a component of the Kerberos network authentication protocol that generates and issues session keys.

Question 17

Match each item with a statement below.
-The information used in conjunction with the algorithm to create the ciphertext from the plaintext.

Accepted Answer

The information used in conjunction with the algorithm to create the ciphertext from the plaintext is referred to as the cryptovariable, commonly known as the key.

Question 18

Match each item with a statement below.
-The entire range of values that can possibly be used to construct an individual key.

Accepted Answer

Keyspace refers to the entire range of values that can possibly be used to construct an individual key.

Answer: H
 An algorithm is a procedure or set of rules used for encryption and decryption.

Answer: G
 Deciphering refers to the process of converting ciphertext back to plain text.

Answer: D
 A cryptosystem is a set of cryptographic algorithms used for encryption and decryption.

Answer: E
 Ciphertext refers to the encrypted version of plain text.

Answer: F
 Work factor refers to the amount of computational effort required to perform a cryptographic attack.

Answer: C
 Enciphering refers to the process of converting plain text to ciphertext using an encryption algorithm.

Answer: A
 Cipher refers to a specific method of encryption or decryption.

Answer: I
 Cryptovariable refers to a variable that is used within a cryptographic algorithm to generate a key or to perform encryption or decryption.

Question 19

Match each item with a statement below.
-The mathematical formula or method used to convert an unencrypted message into an encrypted message or vice versa.

Accepted Answer

An algorithm is the mathematical formula or method used to convert an unencrypted message into an encrypted message or vice versa.

Answer: A
 Cipher refers to the actual encryption or decryption process that uses the algorithm and key.

Answer: I
 Cryptovariable refers to the key or set of keys used in the cipher process.

Answer: D
 Cryptosystem refers to the combination of the algorithm and key used in the encryption or decryption process.

Answer: E
 Ciphertext is the resulting encrypted message after the plaintext message has been transformed using the cipher process.

The other choices, B (keyspace), F (work factor), and G (decipher) are related to cryptography but are not the best choices to match with the given statement.

Question 20

____ is the predominant cryptographic authentication and encryption protocol suite in use today.

Accepted Answer

IPSec is the predominant cryptographic authentication and encryption protocol suite in use today. It is commonly used for securing virtual private networks (VPNs), internet communications, and wireless network connections. SHTTP, PKI, and PEM are also encryption and authentication protocols but are not as widely used as IPSec.

Quiz 9: Encryption - The Foundation for the Virtual Private Network

What are three commonly used functions used by encryption algorithms?

An attacker may obtain duplicate texts, one in ciphertext and one in plaintext, which enable the individual to reverse-engineer the encryption algorithm in a ____ attack.

Match each item with a statement below. -The transformation of the individual components (characters, bytes, or bits) of an unencrypted message into encrypted components.

Match each item with a statement below. -The set of transformations necessary to convert an unencrypted message into an encrypted message.

In ____________________ cipher conversion, the bit stream is subjected to a Boolean XOR function against some other data stream, typically a key stream.

In e-commerce, some cryptographic tools can be used to assure that parties to the transaction are authentic, so that they cannot later deny having participated in a transaction, a feature often called ____________________.

Session ____________________ are attacks involving a communication session that has already been established between a server and a client.

PKI systems are based on public key cryptosystems and include digital certificates and certificate ____________________.

Match each item with a statement below. -The amount of effort (usually expressed in units of time) required to perform cryptanalysis on an encoded message.

Match each item with a statement below. -To decrypt or convert ciphertext to plaintext.

____ attacks can be successful when the ciphertext consists of relatively few characters.

____ attacks are collections of brute-force methods that attempt to deduce statistical relationships between the structure of the unknown key and the ciphertext that is the output of the cryptosystem.

Define encryption.

Match each item with a statement below. -To encrypt or convert plaintext to ciphertext.

Match each item with a statement below. -The encrypted or encoded message resulting from an encryption.

____ is a Kerberos service that generates and issues session keys.

Match each item with a statement below. -The information used in conjunction with the algorithm to create the ciphertext from the plaintext.

Match each item with a statement below. -The entire range of values that can possibly be used to construct an individual key.

Match each item with a statement below. -The mathematical formula or method used to convert an unencrypted message into an encrypted message or vice versa.

____ is the predominant cryptographic authentication and encryption protocol suite in use today.