Pregunta 1
Pregunta
What is the purpose of access control list?
Respuesta
-
to enforce a specified security policy
-
to prevent unauthorised access to data
-
to emphasize encryption
-
it is a key distribution center
Pregunta 2
Pregunta
Identify definition of authentication
Respuesta
-
establishes the identity of a subject
-
specifies and enforces that each object is accessed correctly and only by those that are allowed to do so
-
to enforce a specified security policy
-
to emphasize encryption
Pregunta 3
Pregunta
What does Access Control Information cover?
Pregunta 4
Pregunta
What does Access Control Enforcement cover?
Pregunta 5
Pregunta
What does Access Control Decision Function cover?
Pregunta 6
Pregunta
Define a subject of Access Control List
Respuesta
-
an active entity requesting for resource access
-
a passive entity and target of the protection
-
an access control decision function
-
an access control information function
Pregunta 7
Pregunta
Define an object of Access Control List
Respuesta
-
an active entity requesting for resource access
-
a passive entity and target of the protection
-
an access control decision function
-
an access control information function
Pregunta 8
Pregunta
How many types of resource dependent access controls exist?
Pregunta 9
Pregunta
How many types of access control mechanisms exist
Pregunta 10
Pregunta
Find an example of resource dependent access for network access
Respuesta
-
append
-
execute
-
redirected
-
granted
Pregunta 11
Pregunta
Find an example of resource dependent access for file access
Respuesta
-
append
-
execute
-
redirected
-
granted
Pregunta 12
Pregunta
Find incorrect access control goal
Respuesta
-
invalid operations should be permitted
-
every actions should be checked
-
unnecessary access should not be allowed
-
all the above mentioned
Pregunta 13
Pregunta
What is a property of the capability ticket in access control list?
Respuesta
-
Specifies a given subject can perform what operations on what objects
-
Subjects does not grant rights to other subjects
-
Users have only one ticket
-
Access rights given to a subject are valid for forever
Pregunta 14
Pregunta
What is a property of the procedure oriented objects in access control list?
Respuesta
-
Objects are encapsulated, permitting only certain specified accesses via program execution
-
Specifies a given subject can perform what operations on what objects
-
Access rights given to a subject are valid for forever
-
Users have only one ticket
Pregunta 15
Pregunta
What is a property of the procedure oriented objects in access control list?
Respuesta
-
Enforces accesses to an object be done through a trusted interface
-
Specifies a given subject can perform what operations on what objects
-
Access rights given to a subject are valid for forever
-
Users have only one ticket
Pregunta 16
Pregunta
What does multilevel security mean?
Respuesta
-
Classification of information by the level of importance and permission of access by users with different security clearance
-
Classification of information by date and permission of access by users with different security clearance
-
Classification of information by the level of importance and permission of access by users name
-
Classification of information by date and permission of access by users name
Pregunta 17
Pregunta
How many levels are covered in multilevel security
Pregunta 18
Pregunta
No read up (read down) means
Respuesta
-
A subject can only read an object of less or equal security level
-
A subject can only write into an object of greater or equal security level
-
A subject can only read an object of more or equal security level
-
A subject can only write into an object of less or equal security level
Pregunta 19
Pregunta
No write down (write up) means
Respuesta
-
A subject can only read an object of less or equal security level
-
A subject can only write into an object of greater or equal security level
-
A subject can only read an object of more or equal security level
-
A subject can only write into an object of less or equal security level
Pregunta 20
Pregunta
Define a malware attacks
Respuesta
-
Malicious software causes data compromises
-
A browser helper object that detects changes to URL and logs
-
Users are tricked by fraudulent messages into giving out information
-
The lookup of host names is altered to send users to a fraudulent server
Pregunta 21
Pregunta
How many types of authentication schemes exist?
Pregunta 22
Pregunta
Define a change cipher spec
Respuesta
-
All data sent/received by software that uses SSL
-
used to carry handshake messages
-
used to indicates a change in the encryption and authentication of records
-
used to indicate when the connection is about to close
Pregunta 23
Respuesta
-
All data sent/received by software that uses SSL
-
used to carry handshake messages
-
used to indicates a change in the encryption and authentication of records
-
used to indicate when the connection is about to close
Pregunta 24
Pregunta
Which of the following is true about importance of hash functions i. High Computational Load ii. Message Overhead iii. Security Limitations
Respuesta
-
i only
-
none
-
All the mentioned
-
iii only
Pregunta 25
Pregunta
What does “computationally infeasible to find data mapping to specific hash” mean
Respuesta
-
One way property
-
Collision free property
-
Second way property
-
Collision property
Pregunta 26
Pregunta
Which of the following is not property of hash functions?
Pregunta 27
Pregunta
How many types of hash constructions exist?
Pregunta 28
Pregunta
Output length for SHA-1
Pregunta 29
Pregunta
Input length for SHA-1
Pregunta 30
Pregunta
Which construction method support SHA?
Respuesta
-
Schnorr
-
Diffie-Hellman
-
Merkle-Damgard
-
Alice & Bob
Pregunta 31
Pregunta
How many rounds in general hold SHA-1?
Pregunta 32
Pregunta
How many stages hold SHA-1?
Pregunta 33
Pregunta
How many rounds support one stage?
Pregunta 34
Pregunta
Name of the function that SHA-1 use
Respuesta
-
Merkle-Damgard
-
Feistel
-
Schnorr
-
Diffie-Hellman
Pregunta 35
Pregunta
How many types of SHA exist ?
Pregunta 36
Pregunta
How many rounds MD5 hold in general?
Pregunta 37
Pregunta
Which of the following does not refer to security requirements of Hash functions?
Pregunta 38
Pregunta
The purpose of hash function is to
Respuesta
-
Create a message
-
Compress a message
-
Divide a message
-
Conquer a message
Pregunta 39
Pregunta
How many constant keys support SHA algorithm ?
Pregunta 40
Pregunta
Which of the following refers requirement of digital signature?
Respuesta
-
Must be relatively hard to produce
-
Must be relatively hard to recognize
-
Must depend on the message verified
-
Must to be computationally infeasible to forge
Pregunta 41
Pregunta
Which of the following refers requirement of digital signature?
Respuesta
-
Must be relatively hard to produce
-
Must be relatively hard to recognize
-
Must depend on the message verified
-
Must to be practical to save digital signature in storage
Pregunta 42
Pregunta
What is the property of direct digital signature?
Respuesta
-
Assumed receiver has sender’s private key
-
Involves only sender
-
Can encrypt using receiver’s public key
-
Assumed sender has receiver’s private key
Pregunta 43
Pregunta
Which of the following does not refer to characteristics of digital signature?
Respuesta
-
Private/public is generated by receiver
-
A durable private/public key pair
-
A disposable private/public key pair
-
Signature is two numbers, depending on message hash and secret information
Pregunta 44
Pregunta
How many message authentication functions exist?
Pregunta 45
Pregunta
If public key encryption is used
Respuesta
-
Encryption provides no confidence of sender
-
Encryption provides with some level of confidence of sender
-
Encryption provides fully confidence of sender
-
Encryption does not provided at all
Pregunta 46
Pregunta
In public key cryptography sender signs message using their
Respuesta
-
Public key
-
Shared key
-
Private key
-
Third key
Pregunta 47
Pregunta
In public key cryptography sender signs message using their private key, then encrypts with recipient’s
Respuesta
-
Private key
-
Public key
-
Single key
-
Key
Pregunta 48
Pregunta
What is authentication?
Pregunta 49
Pregunta
Define AAA.(triple A)
Respuesta
-
Access After Anyone
-
Authentication Authorization Accounting
-
Authentication Authorization Access
-
Authentication Access Accounting
Pregunta 50
Pregunta
Which of the term refers to authorization?
Respuesta
-
The user identity is a parameter in access control decisions
-
The user identity is recorded when logging security
-
The process of verifying a claimed identity
-
Accounting of service
Pregunta 51
Pregunta
Which of the term refers to accounting?
Respuesta
-
The user identity is a parameter in access control decisions
-
The user identity is recorded when logging security
-
The process of verifying a claimed identity
-
Accounting of service
Pregunta 52
Pregunta
PIN, passwords refer to
Respuesta
-
Something you have
-
Something you know
-
Something you are
-
Combined method
Pregunta 53
Pregunta
Keys, soft tokens refer to
Respuesta
-
Something you have
-
Something you know
-
Something you are
-
Combined method
Pregunta 54
Pregunta
Fingerprint, iris, palm recognition refer to
Respuesta
-
Something you have
-
Something you know
-
Something you are
-
Combined method
Pregunta 55
Pregunta
Combined or multiple methods of authentication are used for
Respuesta
-
Lower level assurance
-
Medium level assurance
-
Higher level assurance
-
Not used at all
Pregunta 56
Pregunta
How many phases are exist in biometric?
Pregunta 57
Pregunta
When fingerprint was developed?
Pregunta 58
Pregunta
What is minutia ?
Pregunta 59
Respuesta
-
TTP certifies trustworthiness of binding public key with its rightful owner’s identity
-
TTP certifies trustworthiness of binding private key with its rightful owner’s
-
To enable the validation and to give legal meaning to digital signature
-
Answers for supporting encryption/decryption algorithms
Pregunta 60
Respuesta
-
TTP certifies trustworthiness of binding public key with its rightful owner’s identity
-
TTP certifies trustworthiness of binding private key with its rightful owner’s identity
-
To enable the validation and to give legal meaning to digital signature
-
Answers for supporting encryption/decryption algorithms
Pregunta 61
Pregunta
Define a Kerberos
Respuesta
-
Trusted third party authentication system and makes no use of public key cryptography
-
TTP certifies trustworthiness of binding private key with its rightful owner’s identity
-
To enable the validation and to give legal meaning to digital signature
-
Answers for supporting encryption/decryption algorithms
Pregunta 62
Pregunta
Which of the following does not refer for Kerberos property
Pregunta 63
Pregunta
What is a security?
Respuesta
-
The protection of information assets through the use of technology, processes, and training
-
The presence of weaknesses or loopholes in systems which may lead (systematically) to cyber attacks
-
Occurs when a system is compromised based on a vulnerability by an unknown exploit
-
Ensures that computer-related assets are accessed only by authorized parties
Pregunta 64
Pregunta
What is a vulnerability?
Respuesta
-
The protection of information assets through the use of technology, processes, and training
-
The presence of weaknesses or loopholes in systems which may lead (systematically) to cyber attack
-
Occurs when a system is compromised based on a vulnerability by an unknown exploit
-
Ensures that computer-related assets are accessed only by authorized parties
Pregunta 65
Pregunta
What is an attack?
Respuesta
-
The protection of information assets through the use of technology, processes, and training
-
Written to take advantage of a vulnerability; could be a piece of software; a technology; or data that can cause damage or change the behavior of a computer
-
The presence of weaknesses or loopholes in systems which may lead (systematically) to cyber attacks.
-
Occurs when a system is compromised based on a vulnerability by an unknown exploit
Pregunta 66
Pregunta
Types of Threats
Respuesta
-
Interception, Interruption, Modification, Fabrication
-
Method, Opportunity, Motive
-
Confidentiality, Integrity, Availability, Authentication
-
Non-repudiation, Authorisation/Access control, Destruction
Pregunta 67
Respuesta
-
Encryption, Software control, Hardware control, Policies and Procedures,Physical control
-
Method, Opportunity, Motive
-
Confidentiality, Integrity, Availability, Authentication
-
Non-repudiation, Authorisation/Access control, Destruction
Pregunta 68
Pregunta
Interception is __
Respuesta
-
Asset lost, unusable,unavailable
-
Unauthorized access
-
Unauthorized change, tamper of data
-
Ex. Unauthorized add data to a DB
Pregunta 69
Pregunta
Security goals are:
Pregunta 70
Pregunta
Confidentiality means
Respuesta
-
messages exchanged across network remains private
-
contents of messages are not modified while in transit
-
determining the identity of entities involved in message exchanges
-
determining the resources that an entities are allowed to access and in what manner
Pregunta 71
Respuesta
-
Punishment makes attackers think twice –Examples include laws and organisational policy
-
Reduce likelihood and save cost of incidents ◦ ( Ex.: Firewalls, router access control list, spam filters, virus scanners)
-
Need alert if breach occurs –Collection of evidence ◦ ( ex.: Audit logs, intrusion detection system, network traffic monitoring)
-
Punishment by taking money
Pregunta 72
Respuesta
-
Punishment makes attackers think twice –Examples include laws and organisational policy
-
Reduce likelihood and save cost of incidents ◦ ( Ex.: Firewalls, router access control list, spam filters, virus scanners)
-
Need alert if breach occurs –Collection of evidence ◦ ( ex.: Audit logs, intrusion detection system, network traffic monitoring)
-
Punishment by taking money
Pregunta 73
Respuesta
-
Punishment makes attackers think twice –Examples include laws and organisational policy
-
Reduce likelihood and save cost of incidents ◦ ( Ex.: Firewalls, router access control list, spam filters, virus scanners)
-
Need alert if breach occurs –Collection of evidence ◦ ( ex.: Audit logs, intrusion detection system, network traffic monitoring)
-
Punishment by taking money
Pregunta 74
Respuesta
-
messages exchanged across network remains private
-
contents of messages are not modified while in transit
-
determining the identity of entities involved in message exchanges
-
determining the resources that an entities are allowed to access and in what manner
Pregunta 75
Pregunta
Authentication means
Respuesta
-
messages exchanged across network remains private
-
contents of messages are not modified while in transit
-
determining the identity of entities involved in message exchanges
-
determining the resources that an entities are allowed to access and in what manner
Pregunta 76
Pregunta
Non-repudiation means
Respuesta
-
messages exchanged across network remains private
-
contents of messages are not modified while in transit
-
determining the identity of entities involved in message exchanges
-
ensures that parties cannot deny having sent messages
Pregunta 77
Respuesta
-
Demand Encryption Standard
-
Data Encryption Standard
-
Digital Encryption Standard
-
Database Encryption Standard
Pregunta 78
Pregunta
When DES released?
Pregunta 79
Pregunta
Who introduced idea of substitution-permutation (S-P) networks?
Respuesta
-
Shannon
-
Feistal
-
Lucifer
-
Rijndael
Pregunta 80
Pregunta
In how many rounds DES encryption is handled?
Pregunta 81
Pregunta
_____ process messages in blocks, each of which is then encrypted/decrypted?
Respuesta
-
block ciphers
-
stream ciphers
-
mode ciphers
-
code ciphers
Pregunta 82
Pregunta
What is the cryptography?
Respuesta
-
study about how hacker should behave
-
study of encryption principles/methods
-
study about message transformation
-
study of the computer system
Pregunta 83
Pregunta
Which cipher is described below: “Each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet.”
Respuesta
-
Playfair Cipher
-
Vigenere Cipher
-
Caesar Cipher
-
Kerberos
Pregunta 84
Pregunta
How Cryptography is divided by the way in which plaintext is processed:
Pregunta 85
Pregunta
What is the Key Matrix size in Playfair
Pregunta 86
Pregunta
Using the Caesar cipher decrypt this message “Vwdb kxqjub, vwdb irrolvk” (key=2)
Pregunta 87
Pregunta
3 Ds of Security: (DDD)
Respuesta
-
Defence, Deterrence, Detection
-
Data, Development, Device
-
Database, Data, Deadline
-
Demand, Design, Decision
Pregunta 88
Pregunta
MOM stands for ____
Respuesta
-
Method, Opportunity, Motive
-
Modification, Operation, Motto
-
Malfunction, Opinion, Management
-
Messages, Opportunity, Monitoring
Pregunta 89
Pregunta
DES is a symmetric cipher
Pregunta 90
Pregunta
Block size of DES
Respuesta
-
256-bits
-
128-bits
-
64-bits
-
32-bits
Pregunta 91
Respuesta
-
Advanced Encryption Standard
-
Advanced Encryption System
-
American Encryption Standard
-
Alias Encryption Standard
Pregunta 92
Pregunta
Advanced Encryption Standard(AES) also known like
Pregunta 93
Pregunta
Who introduce idea of substitution-permutation?
Respuesta
-
David Shannon
-
Andre Shannon
-
Petre Shannon
-
Claude Shannon
Pregunta 94
Pregunta
In which year was introduced idea of substitution-permutation?
Pregunta 95
Pregunta
What is the plaintext?
Pregunta 96
Pregunta
What is not the model of the symmetric cipher?
Respuesta
-
conventional / private-key / single-key
-
sender and recipient share a common key
-
all classical encryption algorithms are private-key
-
was only type prior to invention of public- key in 1982’s
Pregunta 97
Pregunta
What is the Cipher ?
Pregunta 98
Pregunta
What is the cryptanalysis (codebreaking ) ?
Respuesta
-
algorithm for transforming plaintext to cipher text
-
study of principles/methods of deciphering cipher text without knowing key
-
original message
-
study of encryption principles/methods
Pregunta 99
Pregunta
What is the cryptology?
Respuesta
-
field of both cryptography & cryptanalysis
-
original message
-
study of encryption principles/methods
-
algorithm for transforming plaintext to cipher text
Pregunta 100
Pregunta
What are the general approaches for Cryptanalysis?
Respuesta
-
cryptanalytic attack/brute force attack
-
substitution/transposition
-
permutation/transposition
-
substitution/permutation
Pregunta 101
Pregunta
What is Ciphertext only?
Respuesta
-
attacker knows suspects plaintext/ciphertext
-
only know algorithm & ciphertext, is statistical, must know or be able to identify plaintext
-
attacker selects plaintext and gets ciphertext
-
attacker selects ciphertext and gets plaintext
Pregunta 102
Pregunta
How many types of threats exist?
Pregunta 103
Pregunta
Authorisation means
Respuesta
-
messages exchanged across network remains private
-
contents of messages are not modified while in transit
-
defining the identity of entities involved in message exchanges
-
determining the resources that an entities are allowed to access and in what manner
Pregunta 104
Respuesta
-
Confidentiality, invalid, availability
-
Confidentiality, interact, access
-
Certain, integrity,availability
-
Confidentiality, integrity, availability
Pregunta 105
Respuesta
-
The presence of weaknesses or loopholes in systems which may lead (systematically) to cyber attacks. A weak link in the software, settings, etc., through which, if not fixed early, someone can get access to the computer, application, and/or network and can cause damage
-
Typical threats include unauthorised access, destruction, system overrun and takeover, propagation of malicious code, data thieving and fabrication;
-
Written to take advantage of a vulnerability; could be a piece of software; a technology; or data that can cause damage or change the behavior of a computer
-
Occurs when a system is compromised based on a vulnerability by an unknown exploit
Pregunta 106
Pregunta
What is ciphertext?
Pregunta 107
Respuesta
-
converting plaintext to ciphertext
-
recovering ciphertext from
-
info used in cipher known only to sender/receiver
-
algorithm for transforming plaintext to ciphertext
Pregunta 108
Pregunta
What is encipher (encrypt)?
Respuesta
-
study of encryption principles/methods
-
study of principles/ methods of deciphering ciphertext without knowing key
-
original message
-
converting plaintext to ciphertext
Pregunta 109
Pregunta
What is decipher (decrypt)?
Respuesta
-
converting plaintext to ciphertext
-
recovering ciphertext from plaintext
-
coded message
-
original message
-
recovering plaintext from ciphertext
Pregunta 110
Pregunta
Mostly used symmetric cipher
Pregunta 111
Pregunta
Possible length of AES key
Respuesta
-
128 156 198
-
128 192 256
-
128 184 228
-
128 164 256
Pregunta 112
Pregunta
How many stages has final round of AES?
Pregunta 113
Pregunta 114
Pregunta
What is TRUE about RSA? Each user generates a public/private key pair by:
Respuesta
-
selecting two large primes at random: p, q
-
selecting two small primes at random: p, q
-
selecting three large primes at random: p, q, r
-
selecting only one number at random: p
Pregunta 115
Pregunta
In RSA security relies on a ___ difference in difficulty between ___ (en/decrypt) and ___ (cryptanalyse) problems
Respuesta
-
large enough, easy, hard
-
small enough, hard, easy
-
small enough, easy, hard
-
large enough, hard, easy
Pregunta 116
Pregunta
Advanced Encryption Standard (AES), has three different configurations with respect to number of rounds and
Respuesta
-
Data Size
-
Round Size
-
Key Size
-
Encryption Size
Pregunta 117
Pregunta
_______ is a round cipher based on the Rijndael algorithm that uses a 128-bit block of data.
Pregunta 118
Pregunta
In asymmetric key cryptography, the private key is kept by
Pregunta 119
Pregunta
RSA was developed by:
Respuesta
-
Dr.Tahir El-Gamal
-
Diffie-Hellman
-
Shannon
-
Rivest, Shamir, Adleman
Pregunta 120
Pregunta
Encryption by receiver with sender’s public key:
Respuesta
-
C = Me mod N
-
M=Cd mod N
-
Ya=Xa mod Q
-
C=Km mod Q
Pregunta 121
Pregunta
RSA was founded in:
Pregunta 122
Pregunta
Decryption by sender with sender’s public key:
Respuesta
-
C=Me mod N
-
M=Cd mod N
-
Ya=Xa mod Q
-
C=Km mod Q
Pregunta 123
Pregunta
Calculate n and φ, if p = 3, and q = 11 (RSA)
Respuesta
-
n = 33, φ = 20
-
n = 20, φ = 33
-
n = 33, φ = 33
-
n = 33, φ = 22
Pregunta 124
Pregunta
Calculate n and φ, if p = 17, and q = 11 (RSA)
Respuesta
-
n = 187, φ = 160
-
n = 160, φ = 187
-
n = 187, φ = 187
-
n = 187, φ = 170
Pregunta 125
Pregunta
Calculate C (ciphertext), if p = 3, q = 11, e = 7, M = 2 (RSA)
Respuesta
-
C = 29
-
C = 3
-
C = 22
-
C = 2
Pregunta 126
Pregunta
Calculate M (plaintext), if p = 3, q = 11, d = 3, C = 29 (RSA)
Respuesta
-
M = 2
-
M = 29
-
M = 30
-
M = 1
Pregunta 127
Pregunta
Block size of AES plaintext:
Pregunta 128
Pregunta
Maximum AES number of rounds:
Pregunta 129
Pregunta
AES size of output(output parameter):
Pregunta 130
Pregunta
First public-key type scheme proposed by Diffie & Hellman in
Pregunta 131
Pregunta
Value of key depends on the: (Diffie & Hellman)
Respuesta
-
Participants
-
Keys
-
Message
-
Algorithm
Pregunta 132
Pregunta
If Alice and Bob subsequently communicate, they will have the____ key
Respuesta
-
Same
-
Different
-
Private
-
Public
Pregunta 133
Pregunta
Which of these are true about “a public-key distribution scheme ”?
Respuesta
-
cannot be used to exchange an arbitrary message
-
rather it can establish a common key
-
known only to the two participants
-
all of above
Pregunta 134
Pregunta
When by Diffie & Hellman along with the exposition of public key concepts?
Respuesta
-
1977
-
1978
-
1979
-
none of them
Pregunta 135
Pregunta
Which of them uses two keys( public and private):
Respuesta
-
RSA
-
Caesar
-
Vigenere
-
Playfair
Pregunta 136
Pregunta
A related private-key, known
Respuesta
-
only to the recipient
-
only to the sender
-
none of them
-
to everyone
Pregunta 137
Pregunta
The key must be kept secret for
Pregunta 138
Pregunta
The _________ attack can endanger the security of the Diffie-Hellman method if two parties are not authenticated to each other.
Respuesta
-
man-in-the-middle
-
ciphertext attack
-
plaintext attack
-
none of the above
Pregunta 139
Pregunta
“Using only a subset of letters/words in a longer message marked in some way ” is__
Respuesta
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Caesar Cipher
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RSA
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DES
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Steganography
Pregunta 140
Pregunta
For which cipher an example is given: “Say hi to IITU” After encrypt “Yas ih ot UTII”
Respuesta
-
Playfair Cipher
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Transposition Cipher
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Route Cipher
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Steganography
Pregunta 141
Pregunta
Polyalphabetic substitution ciphers improve security using multiple cipher alphabets
Pregunta 142
Pregunta
For RSA to work, value of P must be less than value of:
Pregunta 143
Pregunta
In symmetric key cryptography, key used by sender and receiver is:
Respuesta
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shаrеd
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Different
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Two keys are used
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None
Pregunta 144
Pregunta
In symmetric-key cryptography, same key is used by:
Respuesta
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One Party
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Multi Party
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Third Party
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Both Party
Pregunta 145
Respuesta
-
Rivеst, Shаmir,, Аdlеmаn
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Roger, Shamir, Adrian
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Robert, Shamir, Anthoney
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Rivest, Shaw, Adleman
Pregunta 146
Pregunta
Which of them is first public-key type scheme?
Respuesta
-
Diffiе & Hеllmаn
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Elgamal
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RSA
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AES
Pregunta 147
Pregunta
When Diffie & Hellman protocol was invented?
Pregunta 148
Pregunta
In Diffie & Hellman key exchange a public key is known only to the two participants
Pregunta 149
Pregunta
In Diffie & Hellman key exchange a public key is cannot be used to exchange an arbitrary message
Pregunta 150
Pregunta
Diffie & Hellman key exchange based on exponentiation in a finite (Galois) fields
Pregunta 151
Pregunta
In Diffie & Hellman protocol when the user A generates their key a secret key should be
Respuesta
-
XА < q
-
generated randomly
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given by user B
-
none
Pregunta 152
Pregunta
Choose the correct formula for computing public key YA in Diffie & Hellman protocol
Respuesta
-
YА= а mod q
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BA = a + b
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CA = a – b
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DA = a * b
Pregunta 153
Pregunta
Choose the correct formula for computing secret key K by user A in Diffie & Hellman protocol
Respuesta
-
K = (YА)^X А mod q
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S = a + b
-
D = a * b
-
L = a * b + 2
Pregunta 154
Pregunta
Elgamal cryptography uses exponentiation in a finite (Galois) fields
Pregunta 155
Pregunta
In the Elgamal cryptography when the user A generates their key a secret key should be
Respuesta
-
1 < XА < q-1
-
generated randomly
-
given by user
-
none
Pregunta 156
Pregunta
Choose the correct formula for computing public key YA in Elgamal cryptography
Respuesta
-
YА = аXА mod q
-
K = YАk mod q
-
K = (YА)^X А mod q
-
YА= а mod q
Pregunta 157
Pregunta
Choose the correct formula for computing one-time key K in Elgamal cryptography
Respuesta
-
K = YАk mod q
-
S = a + b + 1
-
D = a * b + 2
-
L = a * b + 3
Pregunta 158
Pregunta
Choose the correct formula for computing C1 in Elgamal cryptography
Respuesta
-
C1 = аk mod q
-
C3 = a mod b
-
C = z + 2 + 5
-
C5 = a * b +2
Pregunta 159
Pregunta
Choose the correct formula for computing C2 in Elgamal cryptography
Respuesta
-
C2 = KM mod q
-
C = MK
-
C3 = AK
-
C4 = AA
Pregunta 160
Pregunta
In Elgamal cryptography public key cryptosystem related to D-H
Pregunta 161
Pregunta
Known plaintext is...
Respuesta
-
attacker knows suspects plaintext/ciphertext
-
only know algorithm & ciphertext, is statistical, must know or be able to identify plaintext
-
attacker selects plaintext and gets ciphertext
-
attacker selects ciphertext and gets plaintext
-
Attacker selects plaintext or ciphertext to en/decrypt
Pregunta 162
Pregunta
Chosen plaintext is...
Respuesta
-
attacker knows suspects plaintext/ciphertext
-
only know algorithm & ciphertext, is statistical, must know or be able to identify plaintext
-
attacker selects plaintext and gets ciphertext
-
attacker selects ciphertext and gets plaintext
-
Attacker selects plaintext or ciphertext to en/decrypt
Pregunta 163
Pregunta
Chosen ciphertext is...
Respuesta
-
attacker knows suspects plaintext/ciphertext
-
only know algorithm & ciphertext, is statistical, must know or be able to identify plaintext
-
attacker selects plaintext and gets ciphertext
-
attacker selects ciphertext and gets plaintext
-
Attacker selects plaintext or ciphertext to en/decrypt
Pregunta 164
Pregunta
Chosen text is ...
Respuesta
-
attacker knows suspects plaintext/ciphertext
-
only know algorithm & ciphertext, is statistical, must know or be able to identify plaintext
-
attacker selects plaintext and gets ciphertext
-
attacker selects ciphertext and gets plaintext
-
attacker selects plaintext or ciphertext to en/decrypt