What are the general equations for encryption and decryption in the affine cipher?

What are the general equations for encryption and decryption in the affine cipher?

Answer:

E(x)= ax+b mod 26
D(y)= E^1 (y-b) mod 26

Describe a relationship between plaintext, encryption, decryption and cipher

Describe a relationship between plaintext, encryption, decryption and cipher

Answer:

text
Ciphertext=Encryption(Plaintext)
Plaintext=Decryption(Ciphertext)

Carlos wants to send a message to Alice so only she can understand it. He also wants to send a message to Bob so only Bob can understand it. How many private keys does Carlos need?

Carlos wants to send a message to Alice so only she can understand it. He also wants to send a message to Bob so only Bob can understand it. How many private keys does Carlos need?

A) 1
B) 2
C) 3
D) 0

Answer: D

The _________ attack can endanger the security of the Diffie-Hellman method if two parties are not authenticated to each other.

The _________ attack can endanger the security of the Diffie-Hellman method if two parties are not authenticated to each other.

A) man-in-the-middle
B) ciphertext attack
C) plaintext attack
D) none of the above

Answer: A

The ________ method provides a one-time session key for two parties.

The ________ method provides a one-time session key for two parties.

A) Diffie-Hellman
B) RSA
C) DES
D) AES

Answer: A

One commonly used public-key cryptography method is the ______ algorithm.

One commonly used public-key cryptography method is the ______ algorithm.

A) RSS
B) RAS
C) RSA
D) RAA

Answer: C

In an asymmetric-key cipher, the receiver uses the ______ key.

In an asymmetric-key cipher, the receiver uses the ______ key.

A) private
B) public
C) either (a) or (b)
D) neither (a) nor (b)

Answer: A

In an asymmetric-key cipher, the sender uses the__________ key.

In an asymmetric-key cipher, the sender uses the__________ key.

A) private
B) public
C) either (a) or (b)
D) neither (a) nor (b)

Answer: A

In a(n) ________ cipher, a pair of keys is used.

In a(n) ________ cipher, a pair of keys is used.

A) symmetric-key
B) asymmetric-key
C) either (a) or (b)
D) neither (a) nor (b)

Answer: B

In a(n) ________, the key is called the secret key.

In a(n) ________, the key is called the secret key.

A) symmetric-key
B) asymmetric-key
C) either (a) or (b)
D) neither (a) nor (b)

Answer: A

In a(n) ________ cipher, the same key is used by both the sender and receiver.

In a(n) ________ cipher, the same key is used by both the sender and receiver.

A) symmetric-key
B) asymmetric-key
C) either (a) or (b)
D) neither (a) nor (b)

Answer: A

The _______ is a number or a set of numbers on which the cipher operates.

The _______ is a number or a set of numbers on which the cipher operates. 

A) cipher
B) secret
C) key
D) none of the above

Answer: C

A combination of an encryption algorithm and a decryption algorithm is called a ________.

A combination of an encryption algorithm and a decryption algorithm is called a ________.

A) cipher
B) secret
C) key
D) none of the above

Answer: A

A(n) _______ algorithm transforms ciphertext to plaintext.

A(n) _______ algorithm transforms ciphertext to plaintext.

A) encryption
B) decryption
C) either (a) or (b)
D) neither (a) nor (b)

Answer: B

A(n) _______ algorithm transforms plaintext to ciphertext.

A(n) _______ algorithm transforms plaintext to ciphertext.

A) encryption
B) decryption
C) either (a) or (b)
D) neither (a) nor (b)

Answer: A

The ________ is the message after transformation.

The ________ is the message after transformation.

A) ciphertext
This is the correct answer.
B) plaintext
C) secret-text
D) none of the above

Answer: A

The ________is the original message before transformation.

The ________is the original message before transformation.

A) ciphertext
This is the correct answer.
B) plaintext
C) secret-text
D) none of the above

Answer: B

This is the name for the issuer of a PKI certificate.

This is the name for the issuer of a PKI certificate. 

a) man in the middle
b) certificate authority
c) Resource Access Control Facility
d) script kiddy

Answer: B

This is an encryption/decryption key known only to the party or parties that exchange secret messages.

This is an encryption/decryption key known only to the party or parties that exchange secret messages. 

a) e-signature
b) digital certificate
c) private key
d) security token

Answer: C

Cryptanalysis is used

Cryptanalysis is used

a) to find some insecurity in a cryptographic scheme
b) to increase the speed
c) to encrypt the data
d) none of the mentioned

Answer: A

What is data encryption standard (DES)?

What is data encryption standard (DES)?

a) block cipher
b) stream cipher
c) bit cipher
d) none of the mentioned

Answer: A

In asymmetric key cryptography, the private key is kept by

In asymmetric key cryptography, the private key is kept by

a) sender
b) receiver
c) sender and receiver
d) all the connected devices to the network

Answer: B

In cryptography, what is cipher?

In cryptography, what is cipher?

a) algorithm for performing encryption and decryption
b) encrypted message
c) both (a) and (b)
d) none of the above

Answer: A

What is Vulnerability?

What is Vulnerability? 

A) protecting the information from disclosure to unauthorized parties.
B) protecting information from being modified by unauthorized parties
C) ensuring that authorized parties are able to access the information when needed
D) flaw in a system that can leave it open to attack

Answer: D

What is Availability?

What is Availability? 

A) protecting the information from disclosure to unauthorized parties.
B) protecting information from being modified by unauthorized parties
C) ensuring that authorized parties are able to access the information when needed
D) flaw in a system that can leave it open to attack

Answer: C

What is Integrity?

What is Integrity?

A) protecting the information from disclosure to unauthorized parties.
B) protecting information from being modified by unauthorized parties
C) ensuring that authorized parties are able to access the information when needed
D) flaw in a system that can leave it open to attack

Answer: B

What is Confidentiality?

What is Confidentiality? 

A) protecting the information from disclosure to unauthorized parties.
B) refers to protecting information from being modified by unauthorized parties
C) ensuring that authorized parties are able to access the information when needed
D) flaw in a system that can leave it open to attack

Answer: A

Alice, Bob, and Carlos want to communicate using symmetric cryptography. How many keys are necessary for all three to send messages to each other so that all three can read each other messages?

Alice, Bob, and Carlos want to communicate using symmetric cryptography. How many keys are necessary for all three to send messages to each other so that all three can read each other messages? 

A) 1
B) 2
C) 3
D) 4

Answer: A

Alice wants to send Bob a secret message. How many keys are necessary (generated) if Alice and Bob are using public key encryption(Asymmetric)?

Alice wants to send Bob a secret message. How many keys are necessary (generated) if Alice and Bob are using public key encryption(Asymmetric)?

A) 1
B) 2
C) 3
D) 4

Answer: D

Best effort end-to-end delivery

Best effort end-to-end delivery 

A) Data link layer
B) Network layer
C) Physical layer
D) Transport layer

Answer: D

Move bits

Move bits 

A) Data link layer
B) Network layer
C) Physical layer
D) Transport layer

Answer: C

Determines route between source and destination

Determines route between source and destination

A) Data link layer
B) Network layer
C) Physical layer
D) Transport layer

Answer: B

Point-to-point delivery

Point-to-point delivery 

A) Data link layer
B) Network layer
C) Physical layer
D) Transport layer

Answer: A

What is Modification?

What is Modification? 

A) Changing without permission
B) Creating a new (illicit) version
C) Capturing without permission or making unauthorized copy
D) Blocking or breaking a pathway (link) of use

Answer: A

What is Fabrication?

What is Fabrication? 

A) Changing without permission
B) Creating a new (illicit) version
C) Capturing without permission or making unauthorized copy
D) Blocking or breaking a pathway (link) of use

Answer: B

What is interruption?

What is interruption? 

A) Changing without permission
B) Creating a new (illicit) version
C) Capturing without permission or making unauthorized copy
D) Blocking or breaking a pathway (link) of use

Answer: D

What is Interception?

What is Interception?

A) Changing without permission
B) Creating a new (illicit) version
C) Capturing without permission or making unauthorized copy
D) Blocking or breaking a pathway (link) of use

Answer: C

The process of transforming a message so its meaning it not obvious is?

The process of transforming a message so its meaning it not obvious is? 

A) Decryption
B) Ciphertext
C) Plaintext
D) Encryption

Answer: D