WorksheetsAnToanBaoMatDe01
Total questions: 70
Worksheet time: 35mins
General objectives of information security
a. All three options
b. Availability
c. Secrecy
d. Integrity
According to Kirchoff's law, the security of the code system depends on what factors
a. Lock
b. Combine the above answers
c. Decoding algorithm
d. Cryptography
System Safety Strategies
a. The weakest connection point, the holisticness
b. Minimum Permission Limits
c. Bottleneck
e. All answers above
d. Protection in depth
Applications of cryptography include
a. Data security, information authentication, digital signature confirmation, key distribution
b. Encryption, information integrity, digital signature generation, lock agreement
c. Data encryption, hash generation, digital signatures, key management
d. Data security, information integrity authentication, digital signatures, and key management
Ways to increase the security of the specification in the code system are
a. Clear text compression masks the relationship between the clear and the code, increasing the dependency between the code and the clear text
b. Increased dependency between the code and the explicit text
c. Clear Text Compression
d. Concealing the relationship between the plaintext and the code
Factors that do not affect the security of a cryptographic system
a. Script length
b. Secret of the lock
c. Encryption and decryption algorithms
d. Computational complexity of the code system
The schema of a cryptographic system with several components
a. 3 different episodes
b. 6 different episodes
c. 5 different episodes
d. 4 different episodes
SKC is understood as
a. Asymmetric key system
b. Line lock code system
c. Symmetric key system
d. Classic key system
PKC is understood as
a. Classic key system
b. Line lock code system
c. Asymmetric key system (public key system)
d. Symmetric key system
There are several main methods for encryption and decryption
a. Two (symmetric key encryption, public-key encryption)
b. Three (symmetric key encryption, non-public encryption, hash function)
c. Four (symmetric key encryption, non-public encryption, hash function, line encryption)
The line lock code system is known as
a. Classic key system
b. Public Key System
c. Symmetric key system
d. Asymmetric key system
According to Shannon, in order to hide the excess of information
a. The code is cluttered and cumbersome
b. Combine the above answers
c. Complex cryptographic algorithms
d. Large length lock
According to Shannon, entropy is understood as
a. Measure the volume of information of a message
b. Combine the above answers
c. Measure Notification Safety
d. Message Transcript Length
The inverse of an integer a in the set Zn is the number
a. Survive under all conditions
b. Real numbers
c. Is an even number
d. Conditional existence
Shannon code system is absolutely safe if
a. Complex cryptographic algorithms
b. Combine the above answers
c. Constantly changing locks
d. The minimum length of the key is equivalent to the message length
In the block code system, use the metric substitution table (s-box) for the calculation expression to
a. Increase the speed of calculation
b. Facilitate programming
c. Combining the above characteristics
d. Difficult to decipher
The secret boxes (s-boxes) of the Des algorithm
a. Inputs with 48-bit strings produce 32-bit strings
b. Inputs with 48-bit strings produce 40-bit strings
c. Inputs with 32-bit strings produce 40-bit strings
d. Inputs with 32-bit strings produce 32-bit strings
Which of the following conclusions is true for DES
a. is a code system with a small key space
b. is an encryption system based on Lucipher code
c. is a low-complexity locking system
d. is the PKC key system
AES has several master keys (master keys)
a. 2
b. 4
c. 5
d. 3
There are several modes of using block codes
a. 2
b. 5
c. 4
d. 3
AES Master Key Length
a. 128 or 256, or 512 bits
b. 64 or 128, or 256 bits
c. 128 or 192, or 256 bits
d. 64 or 192, or 256 bits
Which of the following clauses is wrong
a. DES has 4 weak keys
b. DES has 6 pairs of semi-weak locks
c. DES has 32-bit length child keys
d. DES has 48-bit length subkeys
Number of secret boxes (S-boxes) of DES algorithm
a. 8
b. 12
c. 10
d. 6
Classical encoding systems are ciphers
a. Encode a discrete character or phrase
b. There is a key that is born according to the algorithm
c. Bit Range Encoding
d. Has a large length lock
In the VIGENERE cipher system, if the ASCII character set is applied to the explicit and cipher spaces, with a key of length 10, there will be a number of keys
a. 256^10
b. 10^256
c. 26^10
d. 256*10
With AES encryption with a number of loops
a. 10,16 or 32
b. 8,12 or 14
c. 10,12 or 14
d. 8,16 or 32
AES encryption algorithm uses a master key of 192 lengths with a number of loops
a. 8
b. 14
c. 12
d. 10
Which mode of using block code is common
a. CBC
b. OFB
c. ECB
d. CFB
Which block code usage mode does not use IV (Initialization Vector) values
a. CFB
b. CBC
c. OFB
d. ECB
The AES cipher system has several S-box tables for the encryption process
a. 4
b. 1 Bảng S8
c. 3
d. 2
The algebraic structure of DES causes
a. The key size decreases if the encryption is repeated multiple times with keys of the same size
b. Complexity does not increase if the encryption is repeated multiple times with keys of the same size
c. The key size increases if the encryption is repeated multiple times with keys of the same size
d. Complexity increases if encryption is repeated multiple times with keys of the same size
In the public encryption system, which of the following judgments is true
a. Use the secret key to CIPHER, use the public key to DECRYPT
b. Use two keys generated by the sender
c. Use the public key ENCRYPTION, use the secret key to DECRYPT
d. Use a common secret key for both ciphers
What is wrong in the PKC encryption system
a. Use the public key ENCRYPTION, use the secret key to DECRYPT
b. Use a common secret key for both ciphers
c. Use the secret key to CIPHER, use the public key to DECRYPT
d. Use two keys generated by the sender
The idea of the Knapsack (Merkle-Hellman) encryption system is
a. The difficulty of the problem of analyzing a number into two prime factors
b. Secret fue key encryption system
c. The insolvency of the discrete Logarithmic problem
d. The problem of cartoning
The idea of the RSA encryption system
a. The difficulty of the problem of analyzing a number into two prime factors
b. Secret fue key encryption system
c. The problem of cartoning
d. The insolvency of the discrete Logarithmic problem
The idea of the Elgama encryption system
a. Secret fue key encryption system
b. The problem of cartoning
c. The insolvency of the discrete Logarithmic problem
d. The difficulty of solving the analysis problem
Which of the following encryption systems is not a public encryption system
a. DES
b. RSA
c. Trapdoor
d. Elgama
Which of the following encryption systems is not a secret encryption system
a. Caesar
b. RSA
c. Trapdoor
d. Affine
Which of the following coding systems is not a block coding system
a. Trapdoor
b. DSA
c. AES
d. DES
What is a digital signature
a. Use the same key for both signing and checking signatures
b. Use the secret key to check the signature, the public key to sign
c. Use the secret key to sign, the public key to check the signature
d. A Secret Key Encryption System
1. Which of the following statements is true about digital signatures
a. A public encryption
b. A test in which 1 person can code and only 1 person can test
c. A test in which only those who know the secret key can test the potion
d. A test in which multiple people can check that only one person is signed
Disadvantages of public key systems
a. Narrow lock space is easy to spy on code
b. The method of encryption is public, so it is not secure
c. The public key makes the message content easy to decrypt
d. Slow algorithm processing speed
The encryption model that combines public and secret encryption is used as
a. Using a secret encryption system to encrypt messages, a public encryption system to encrypt messages for the 2nd time
b. Using a secret encryption system that encrypts messages, a public encryption system that encrypts the secret key and transmits it together
c. Using a public encryption system that encrypts messages, a secret encryption system that encrypts a secret key and transmits it together
d. Using a public encryption system to encrypt messages, a secret encryption system to encrypt messages for the 2nd time
The phenomenon of explicit disclosure in the RSA algorithm is understood:
a. The content of the post-encrypted message can be easily inferred from the original message
b. The encoding result does not change from the original message
c. The original message is easily inferred backwards from the encrypted message
d. The original message is easily used by spying methods to deduce
Which conclusion is true for the encryption system on the Elliptic curve
a. Huge lock space
b. Private lock is a point on the curve
c. Complexity of exponential calculations
d. Complexity of prime number analysis calculations
Which conclusion is true for the encryption system on the Elliptic curve
a. The length of the code is equal to the length of the explicit text
b. Combine the above answers
c. Smaller lock length than RSA but secure
d. Computational Algorithms with Power Operations
In a combined system of RSA and AES, the function of the encryption systems is
a. RSA Encrypt Messages, RSA Encrypt RSA Keys
b. AES 1st Encryption Message, 2nd RSA Encryption for Enhanced Security
c. RSA 1st Encrypt Messages, AES 2nd Encryption for Enhanced Security
d. AES Message Encryption, RSA AES Key Encryption
Which conclusion is wrong
a. The ECC encryption system has a smaller key length than RSA
b. The Elgamal encryption system always has the phenomenon of duplicate ciphers
c. The RSA encryption system always exists in the phenomenon of duplicate ciphers
d. The Merkle-Hellman encryption system has a key length of 1
Which conclusion is correct
a. The Merkle - Hellman code system has a small lock
b. The Merkle - Hellman code system has a trap door that is a super tank lock
c. The Merkle-Hellman code system has a trap door that is a public key
d. The Merkle-Hellman code system does not calculate inverse numbers
Which conclusion is wrong
a. The Elgamal encryption system for ciphers that are larger than the spec
b. Elgamal encryption system for ciphers that are twice the size of the spec
c. The Elgamal coding system is based on the difficulty of discrete logarithm problems
d. Elgamal encryption system is widely used
Which conclusion is wrong
a. The Merkle - Hellman code system is based on the difficulty of the problem of placing objects in the box
b. The Merkle-Hellman code system is not widely used
c. The Merkle-Hellman code system has a small key length
d. The Merkle-Hellman code system has low safety
Which conclusion is wrong with the ECC key system
a. ECC with lock is the point on the Elliptic curve
b. ECC performs calculations with points on the Elliptic curve
c. ECC has a smaller key size than RSA
d. ECC is easy to deploy and install
Which conclusion is wrong
a. The RSA code system is widely used in the Internet
b. ECC ciphers are applied in the lock agreement model
c. The Merkle-Hellman code system is not widely used in the Internet
d. The Merkle - Hellman code system is widely used in digital signatures
Compared to the block cipher system, what are the characteristics of the public key cipher system?
a. Has a slow computing speed
b. Publicly encrypted algorithms, so they are not secure
c. Small lock space is easy to spy on code
d. There is a public key, so the content of the message is easily decrypted
Which conclusion is correct
a. The Merkle - Hellman code system is widely used in digital signatures
b. ECC cryptography is applied in digital signatures
c. The Elgamal code system is widely applied in the Internet
d. The Merkle - Hellman code system is widely applied in the Internet
Which conclusion is correct
a. PKC has the same encryption and decryption algorithms
b. The PKC cipher system allows the key encryption of the SKC cipher system
c. PKC stands for Private key cryptography
d. The speed of encryption and decryption in the PKC code system is equivalent
Which conclusion is correct
a. The Merkle-Hellman code system has a super-tank key as a public key
b. The Merkle-Hellman code system has a door contained in the public key
c. Highly secure Merkle - Hellman code system
d. The Merkle-Hellman code system is less secure than RSA
Digital signatures are understood as
a. An inspection in which multiple people can search but only one person is created with a signature
b. A test in which 1 person can code and only 1 person can test
c. A test in which only those who know the secret key can check it
d. A public encryption
To sign a large digital content, we usually do
a. Sign on important parts of digital content
b. Sign on behalf of digital content / Sign on representation of digital content
c. Sign at the end of the document
d. Sign across digital content
RSA digital signatures are similar to the RSA encryption system in several points
a. Using secret and public keys, the secret key is used for encryption, and the public key is used for decryption
b. Use of secret and public keys
c. Use the secret and public keys in the same order of execution
d. Use the same encryption and decryption algorithms
RSA digital signatures differ from the RSA encryption system in several points
a. Use completely different secret and public keys
b. Use the same key pair, but the order in which the key is used is reversed
c. In digital signatures, the role of secret and public keys is unclear
d. Use secret and public keys, but 2 keys are defined completely differently
Indicate the hash function characteristics
a. Explicit encryption
b. Create a constant-length output value
c. With the same input value will obtain different output values
d. Create variable outputs
Which conclusion is true for hash functions
a. A hash function is conventional, a secret key and can be changed by the user
b. A hash function is conventional, a secret key and cannot be changed by the user
c. The hash value is a representation of the input
d. A hash function has the same number of outputs as the number of inputs
DSS Standard Digital Signature Signature Signature Length
a. 320 bit
b. 160 bit
c. 512 bit
d. 128 bit
Which conclusion is true for MD-5 hash function
a. There are 2^128 hash values
b. There are 2*128 hash values
c. Has 128^2 hash values
d. Has 128 hash values
Which conclusion is true for SHA-I hashes
a. 160-bit hash space
b. Has 2^160 hash values
c. Has 160^2 hash values
d. Has 160 hash values
A message has a magnitude of 1024 bytes. After going through the 1st hash, the result is 512 bytes. Ask how many results can we get if we hash 3 times in a row
a. 232 bytes
b. 16 bytes
c. 216 bit
d. 32 bytes
Basis of DSA standard digital signature algorithm
a. ECC Digital Signature Algorithm
b. Elgamal Digital Signature Algorithm
c. RSA Digital Signature Algorithm
d. Merkle-Hellman Digital Signature Algorithm
Which conclusion is true for hash functions
a. The non-collision of MD-5 is equivalent to that of SHA-1
b. Non-collision of MD-5 compared to SHA-1
c. The hash function is used to create user accounts on the network
d. Hash functions are only applied in digital signatures
Blom Key Delivery System Implements
a. Distribute a private function, users build their own shared keys by combining private functions with public keys
b. Distribute each secret key pair to each user in the system
c. Distribute a public key to the entire group of users
d. Distribute each user's secret and public key, the public key is shared with the whole team
