Mock ICT Comprehensive Questions
(Frequently Tested) with Verified
Answers Graded A+
A hacker is attempting to decrypt an encrypted message by analysing the most commonly
occurring characters and comparing them to typical letter distributions in the target language.
Their aim is to reconstruct the original plaintext without knowing the encryption key. Which
cryptanalysis technique is the hacker using in this scenario?
Dictionary Attack
Frequency and pattern analysis
Known Plaintext Attack
Differential Cryptanalysis Attack - Answer: Frequency and pattern analysis
Put the following phases of the Diffie Hellman key Exchange in the correct order:
Alice and Bob can the shared secret key for secure communication.
Alice and Bob agree on a public prime number and a base.
Alice and Bob exchange their public values.
Alice chooses a secret number and calculates her public value. Bob chooses his secret number
and calculates his public value.
Each of them calculates the shared secret key using their private number and the other's public
value.
2, 4, 3, 5, 1
5, 4, 2, 1, 3
3, 1, 4, 2, 5
1, 2, 3, 4, 5 - Answer: 2, 4, 3, 5, 1
, Encrypt the plaintext message "SUCCEED IN FIRST ATTEMPT" using the transposition method
and the secret key "HELLO". The ciphertext is - Answer: UDRTSEI TT CISEC NTMEFAP
What type of attack can be prevented by using ESP in IPSec?
Eavesdropping
Denial of service
Man-in-the-middle
Message replay - Answer: Eavesdropping
What security principles are provided by the cryptographic process shown in the diagram?
It encrypts the message but does not provide any form of authentication.
In addition to digital signature, this method provides both confidentiality and authentication.
It guarantees confidentiality by hashing the message only.
It uses public key encryption to protect the integrity and confidentiality of the hash but does not
use a digital signature to verify the sender's identity - Answer: In addition to digital signature,
this method provides both confidentiality and authentication.
Which encryption algorithm that uses block mode is considered not suitable for sending
images?
Cipher Block Chaining CBC
Data Encryption Standard DES
Rivest Cipher 4 (RC4)
Electronic Code Book ECB - Answer: Electronic Code Book ECB
Alice and Bob would like to communicate securely. Alice aims to provide a mechanism to ensure
the confidentiality of data during transmission, and Bob aims to have a mechanism to confirm
(Frequently Tested) with Verified
Answers Graded A+
A hacker is attempting to decrypt an encrypted message by analysing the most commonly
occurring characters and comparing them to typical letter distributions in the target language.
Their aim is to reconstruct the original plaintext without knowing the encryption key. Which
cryptanalysis technique is the hacker using in this scenario?
Dictionary Attack
Frequency and pattern analysis
Known Plaintext Attack
Differential Cryptanalysis Attack - Answer: Frequency and pattern analysis
Put the following phases of the Diffie Hellman key Exchange in the correct order:
Alice and Bob can the shared secret key for secure communication.
Alice and Bob agree on a public prime number and a base.
Alice and Bob exchange their public values.
Alice chooses a secret number and calculates her public value. Bob chooses his secret number
and calculates his public value.
Each of them calculates the shared secret key using their private number and the other's public
value.
2, 4, 3, 5, 1
5, 4, 2, 1, 3
3, 1, 4, 2, 5
1, 2, 3, 4, 5 - Answer: 2, 4, 3, 5, 1
, Encrypt the plaintext message "SUCCEED IN FIRST ATTEMPT" using the transposition method
and the secret key "HELLO". The ciphertext is - Answer: UDRTSEI TT CISEC NTMEFAP
What type of attack can be prevented by using ESP in IPSec?
Eavesdropping
Denial of service
Man-in-the-middle
Message replay - Answer: Eavesdropping
What security principles are provided by the cryptographic process shown in the diagram?
It encrypts the message but does not provide any form of authentication.
In addition to digital signature, this method provides both confidentiality and authentication.
It guarantees confidentiality by hashing the message only.
It uses public key encryption to protect the integrity and confidentiality of the hash but does not
use a digital signature to verify the sender's identity - Answer: In addition to digital signature,
this method provides both confidentiality and authentication.
Which encryption algorithm that uses block mode is considered not suitable for sending
images?
Cipher Block Chaining CBC
Data Encryption Standard DES
Rivest Cipher 4 (RC4)
Electronic Code Book ECB - Answer: Electronic Code Book ECB
Alice and Bob would like to communicate securely. Alice aims to provide a mechanism to ensure
the confidentiality of data during transmission, and Bob aims to have a mechanism to confirm
