Block ciphers accumulate symbols in a message of a ______.
Fixed size
Variable
Integration
All of the mentioned above
Correct Answer :
A. Fixed size
Block cyphers amass symbols in a message of a fixed size (the block), whereas stream cyphers operate on a stream of symbols that is constantly changing. When a cypher employs the same key for both encryption and decryption, the algorithm or cypher is referred to as a symmetric key algorithm. Asymmetric key algorithms, also known as cyphers, encrypt and decrypt data using a different key for each operation.
Related Questions
The DES (Data Encryption Standard) cipher follows the fiestal structure. Which of the following properties are not shown by the fiestal structure?
The input text is divided into two parts: one being left half and another one being right half.
Swapping of the left and right halves are performed after each round.
The plain text is converted into a matrix form first
None of the above
Using Rivest, Shamir, Adleman cryptosystem with p=7 and q=9. Encrypt M=24 to find ciphertext. The Ciphertext is:
42
93
114
103
Hash functions are mathematical functions that transform or map a given set of data into a bit string of fixed size, also known as the hash value.
Hash value
Map value
Both A and B
None of the mentioned above
Codes and ciphers are different ways to _____ a message.
Encrypt
Decrypt
Both A and B
All of the mentioned above
Which of the following security attacks is not an active attack? ORWhich of the following attacks is a passive attack?
Masquerade
Modification of message
Denial of service
Traffic analysis
Conventional cryptography also known as ... encryption.
asymmetric-key
logical-key
symmetric-key
None of these
Which of the following is the main disadvantage of the ECB (Electronic Code Book)?orWhich of the following is the major drawback of ECB?
It requires large block size
Padding is done to make the plain text divisible into blocks of fixed size
It is prone to cryptanalysis since there is a direct relationship between plain text and cipher text.
None of the above
In the AES-128 algorithm there are mainly __________ similar rounds and _________ round is different from other round.
5 similar rounds having 2 pair ; every alternate
9 ; the last
8 ; the first and last
10 ; no
A key is a string of bits used by a cryptographic algorithm to transform plain text into ciphertext. Which of the following is capable of becoming a key in a cryptographic algorithm?
An integer values
A square matrix
An array of characters (i.e. a string)
All of the above
How many elements are used in cryptography tools?
1
4
6
3
Which one of the following algorithms is not used in asymmetric-key cryptography?
DSA algorithm
Electronic code book algorithm
Diffie-Hellman algorithm
RSA algorithm
For which of the following should EBC (Electronic Code Book) process not be used for encryption?
For large block sizes
For fixed block sizes
For small block sizes
None of the above
In Cipher block chaining mode, the current plaintext block is added to the ____.
Previous ciphertext block
Next ciphertext block
Middle ciphertext block
None of the mentioned above
Which is the cryptographic protocol that is used to protect an HTTP connection?
Resource reservation protocol
SCTP
TLS
ECN
Security Goals of Cryptography are
Confidentiality
Authenticityn
Data integrityn
All of these
Which of the following cipher techniques include the involvement of matrix operations in their algorithms of encryption and decryption?
Hill Cipher
Playfair cipher
Both a and b
None of the above
Which of the following is a mode of operation for the Block ciphers in cryptography?
Electronic Code Book (ECB)
Cipher Block Chaining (CBC)
Counter (CTR) mode
All of the above
Hash functions are used in ___ and have variable levels of complexity and difficulty.
System approach
Cyber safe
Cryptography
None of the mentioned above
When a hash function is used to provide message authentication, the hash function value is called to as:
Message Field
Message Digest
Message Score
Message Leap
Block ciphers accumulate symbols in a message of a ______.
Fixed size
Variable
Integration
All of the mentioned above
What is the block size of plain text in SHA- 512 algorithm?
512 bits
1024 bits
2048 bits
None of the above
Study with quantum computers of future being expected to solve the discrete logarithmic problem and the popularly know cryptography methods such as AES, RSA, DES, quantum cryptography becomes which solution?
Quantum Solution
Foreseen Solution
Cryptographic Solution
Block Cipher Solution
Which of the following modes of operation in DES is used for operating?
Cipher Feedback Mode (CFB)
Cipher Block chaining (CBC)
Electronic code book (ECB)
Output Feedback Modes (OFB)
How many sub-keys in the total are used by the IDEA for encrypting the plain text into ciphertext?
64 sub- keys
48 sub- keys
52 sub- keys
Only one key and no subkeys
You are supposed to use hill cipher for encryption technique. You are provided with the following matrix,
Is the given matrix 'A', a valid key to be used for encryption?
Yes
No
Can't be determined
Data insufficient
Among the following given options, chose the strongest encryption technique?
DES ( Data Encryption Standard)
Double DES
Triple DES
AES (Advance Encryption Standard)
All the below-stated processes are performed in the AES (Advanced Encryption Standard) Algorithm. Which of the following process(s) are not performed in the final round of the AES?
a) Substitution bytes
b) Shift rows
c) Mix columns
d) Add round key
Options
i.
iii.
All of the mentioned
None of the mentioned
Cipher Feedback Mode is given as feedback to the ____ of encryption with some new specifications.
Next block
Previous block
Middle block
All of the mentioned above
What is the full-form of RSA in the RSA encryption technique?
Round Security Algorithm
Rivest, Shamir, Adleman
Robert, Shamir, Addie
None of the above
____ is the message or data that can be readable by the sender.
Edited
Main Text
Plain text
All of the mentioned above