CRY302 - Multi, Only true- mrjohn
2. Joseph Mauborgne proposed an improvement to the Vernam cipher that uses a random key that is as long as the message so that the key does not need to be repeated. The key is used to encrypt and decrypt a single message and then is discarded. Each new message requires a new key of the same length as the new message. This scheme is known as a(n) __________ . A) pascaline B) one-time pad C) polycipher D) enigma
b
20. A loss of __________ is the unauthorized disclosure of information. A) authenticity B) confidentiality C) reliability D) integrity
b
23. A __________ takes place when one entity pretends to be a different entity. A) replay B) masquerade C) service denial D) passive attack
b
25. A(n) __________ service is one that protects a system to ensure its availability and addresses the security concerns raised by denial- of- service attacks. A) replay B) availability C) masquerade D) integrity
b
29. Data appended to, or a cryptographic transformation of, a data unit that allows a recipient of the data unit to prove the source and integrity of the data unit and protect against forgery is a(n) ___________ . A) security audit trail B) digital signature C) encipherment D) authentication exchange
b
3. An original intelligible message fed into the algorithm as input is known as _________ , while the coded message produced as output is called the __________ . A) decryption, encryption B) plaintext, ciphertext C) deciphering, enciphering D) cipher, plaintext
b
4. The vast majority of network-based symmetric cryptographic applications make use of ________ ciphers. A) linear B) block C) permutation D) stream
b
45. __________ techniques map plaintext elements (characters, bits) into ciphertext elements. A) Transposition B) Substitution C) Traditional D) Symmetric
b
46. Joseph Mauborgne proposed an improvement to the Vernam cipher that uses a random key that is as long as the message so that the key does not need to be repeated. The key is used to encrypt and decrypt a single message and then is discarded. Each new message requires a new key of the same length as the new message. This scheme is known as a(n) __________ . A) pascaline B) one-time pad C) polycipher D) enigma
b
49. __________ attacks exploit the characteristics of the algorithm to attempt to deduce a specific plaintext or to deduce the key being used. A) Brute-force B) Cryptanalytic C) Block cipher D) Transposition
b
7. Key sizes of __________ or less are now considered to be inadequate. A) 128 bits B) 32 bits C) 16 bits D) 64 bits
b
7. The ___________ takes the ciphertext and the secret key and produces the original plaintext. It is essentially the encryption algorithm run in reverse. A) Voronoi algorithm B) decryption algorithm C) cryptanalysis D) diagram algorithm
b
9. The criteria used in the design of the __________ focused on the design of the S-boxes and on the P function that takes the output of the S-boxes. A) Avalanche Attack B) Data Encryption Standard C) Product Cipher D) Substitution Key
b
9. __________ attacks exploit the characteristics of the algorithm to attempt to deduce a specific plaintext or to deduce the key being used. A) Brute-force B) Cryptanalytic C) Block cipher D) Transposition
b
11. The function F provides the element of __________ in a Feistel cipher. A) clarification B) alignment C) confusion D) stability
c
12. _________ refer to common two-letter combinations in the English language. A) Streaming B) Transposition C) Digrams D) Polyalphabetic cipher
c
13. A way to improve on the simple monoalphabetic technique is to use different monoalphabetic substitutions as one proceeds through the plaintext message. The general name for this approach is ___________ . A) rail fence cipher B) cryptanalysis C) polyalphabetic substitution cipher D) polyanalysis cipher
c
13. Mister and Adams proposed that all linear combinations of S-box columns should be _________ which are a special class of Boolean functions that are highly nonlinear according to certain mathematical criteria. A) horizontal functions B) angular functions C) bent functions D) vertical functions
c
15. Allowing for the maximum number of possible encryption mappings from the plaintext block is referred to by Feistel as the __________ . A) ideal substitution cipher B) round function C) ideal block cipher D) diffusion cipher
c
16. __________ is the most common method used to conceal small blocks of data, such as encryption keys and hash function values, which are used in digital signatures. A) Symmetric encryption B) Data integrity algorithms C) Asymmetric encryption D) Authentication protocols
c
28. The protection of the information that might be derived from observation of traffic flows is _________ . A) connectionless confidentiality B) connection confidentiality C) traffic- flow confidentiality D) selective- field confidentiality
c
48. Techniques used for deciphering a message without any knowledge of the enciphering details is ___________ . A) blind deciphering B) steganography C) cryptanalysis D) transposition
c
51. _________ refer(s) to common two-letter combinations in the English language. A) Streaming B) Transposition C) Digrams D) Polyalphabetic cipher
c
52. A way to improve on the simple monoalphabetic technique is to use different monoalphabetic substitutions as one proceeds through the plaintext message. The general name for this approach is ___________ . A) rail fence cipher B) cryptanalysis C) polyalphabetic substitution cipher D) polyanalysis cipher
c
6. Techniques used for deciphering a message without any knowledge of the enciphering details is ___________ . A) blind deciphering B) steganography C) cryptanalysis D) transposition
c
10. The greater the number of rounds, the __________ it is to perform cryptanalysis. A) easier B) less difficult C) equally difficult D) harder
d
24. __________ is the protection of transmitted data from passive attacks. A) Access control B) Data control C) Nonrepudiation D) Confidentiality
d
26. __________ threats exploit service flaws in computers to inhibit use by legitimate users. A) Information access B) Reliability C) Passive D) Service
d
3. A __________ cipher is one that encrypts a digital data stream one bit or one byte at a time. A) product B) block C) key D) stream
d
5. A __________ cipher is one in which a block of plaintext is treated as a whole and used to produce a ciphertext block of equal length. A) bit B) product C) stream D) block
d
65. A __________ cipher is one that encrypts a digital data stream one bit or one byte at a time. A) product B) block C) key D) stream
d
8. Feistel proposed that we can approximate the ideal block cipher by utilizing the concept of a __________ cipher, which is the execution of two or more simple ciphers in sequence in such a way that the final result or product is cryptographically stronger than any of the component ciphers. A) linear B) permutation C) differential D) product
d
8. If both sender and receiver use the same key, the system is referred to as: A) public-key encryption B) two-key C) asymmetric D) conventional encryption
d
1. The Diffie-Hellman key exchange is a simple public-key algorithm.
t
1.Message authentication is a mechanism or service used to verify the integrity of a message.
t
1.The principle requirement of random or pseudorandom number generation is that the generated number stream be unpredictable.
t
1.Virtually all cryptographic hash functions involve the iterative use of a compression function.
t
10. For determining the security of various elliptic curve ciphers it is of some interest to know the number ofpoints in a finite abelian group defined over an ellipticcurve.
t
10. If the authenticator is encrypted with the sender's private key, itserves as a signature that verifies origin, content, and sequencing.
t
10. If the calculated frame check sequence is equal to the incomingframe check sequence the message is considered authentic.
t
10. Three broad categories of cryptographic algorithms are commonlyused to create PRNGs:symmetric block ciphers, asymmetricciphers, and hash functions and message authentication codes.
t
11. A trap-door one-way function is easy to calculate in one directionand infeasible to calculate in the other direction unless certainadditional information is known.
t
11. A widely used technique for pseudorandom number generation is an algorithm known as the linear congruential method.
t
11. The form of cubic equation appropriate for cryptographic applications for elliptic curves is somewhat different for GF(2m) than for Zp.
t
12. A CTR-based authenticated encryption approach is the mostefficient mode of operation for high-speed packet networks.
t
13. Before the application of the public-key cryptosystem eachparticipant must generate a pair of keys.
t
13. The security of Blum, Blum, Shub is based on the difficulty of factoring n.
t
13. The security of ECC depends on how difficult it is to determine k given kP and P.
t
14. As with encryption algorithms and hash functions cryptanalyticattacks on MAC algorithms seek to exploit some property of thealgorithm to perform some attack other than an exhaustivesearch.
t
14. The defense against the brute-force approach for RSA is to use alarge key space.
t
15. The longer the keyword the more difficult the cryptanalysis.
t
15. To attack MD5, the attacker can choose any set of messages andwork on these offline on a dedicated computing facility to find acollision.
t
15.Since a symmetric block cipher produces an apparently random output it can serve as the basis of a pseudorandom number generator.
t
2.A good hash function has the property that the results of applying the function to a large set of inputs will produce outputs that are evenly distributed and apparently random.
t
2.Random numbers play an important role in the use of encryption for various network security applications.
t
2.The security of ElGamal is based on the difficulty of computing discrete logarithms.
t
3.Asymmetric encryption transforms plaintext into ciphertext.
t
3.The MAC does not provide a digital signature because both sender and receiver share the same key.
t
3.There are well-defined tests for determining uniform distribution and independence to validate that a sequence of numbers is random.
t
4.Hash functions can be used for intrusion and virus detections.
t
4.The Diffie-Hellman algorithm depends on the difficulty of computing discrete logarithms for its effectiveness.
t
4.With true random sequences each number is statistically independent of other numbers in the sequence and therefore unpredictable.
t
5.A major advance in symmetric cryptography occurred with the development of the rotor encryption/decryption machine.
t
5.One means of forming a MAC is to combine a cryptographic hash function in some fashion with a secret key.
t
5.The true random number generator may simply involve conversion of an analog source to a binary output.
t
5.Whirlpool is a popular cryptographic hash function.
t
6.Most of the products and standards that use public-key cryptography for encryption and digital signatures use RSA.
t
7.If the PRF does not generate effectively random 128-bit output values it may be possible for an adversary to narrow the possibilities and successfully use a brute force attack.
t
7.Message authentication may also verify sequencing and timeliness.
t
7.Much of the theory of public-key cryptosystems is based on number theory.
t
8.A number of public-key ciphers are based on the use of an abelian group.
t
8.Asymmetric algorithms rely on one key for encryption and a different but related key for decryption.
t
8.The security of any MAC function based on an embedded hash function depends in some way on the cryptographic strength of the underlying hash function.
t
9.The seed that serves as input to the PRNG must be secure for cryptographic applications.
t
18. __________ involves the passive capture of a data unit and its subsequent retransmission to produce an unauthorized effect. A) Disruption B) Replay C) Service denial D) Masquerade
b
17. A common technique for masking contents of messages or other information traffic so that opponents can not extract the information from the message is __________ . A) integrity B) encryption C) analysis D) masquerade
b
1. DES exhibits the classic __________ block cipher structure, which consists of a number of identical rounds of processing. A) Feistel B) SAC C) Shannon D) Rendell
a
11. The __________ attack is the easiest to defend against because the opponent has the least amount of information to work with. A) ciphertext-only B) chosen ciphertext C) known plaintext D) chosen plaintext
a
12. One of the most intense areas of research in the field of symmetric block ciphers is __________ design. A) S-box B) F-box C) E-box D) D-box
a
14. A technique referred to as a __________ is a mapping achieved by performing some sort of permutation on the plaintext letters. A) transposition cipher B) polyalphabetic cipher C) Caesar cipher D) monoalphabetic cipher
a
14. The Nyberg approach that is more or less a manual approach with only simple mathematics to support it is __________ . A) human-made B) random C) math-made D) random with testing
a
15. The methods of __________ conceal the existence of the message in a graphic image. A) steganography B) decryptology C) cryptology D) cryptography
a
19. The three concepts that form what is often referred to as the CIA triad are ________ . These three concepts embody the fundamental security objectives for both data and for information and computing services. A) confidentiality, integrity and availability B) communication, integrity and authentication C) confidentiality, integrity, access control D) communication, information and authenticity
a
2. A sequence of plaintext elements is replaced by a __________ of that sequence which means that no elements are added, deleted or replaced in the sequence, but rather the order in which the elements appear in the sequence is changed. A) permutation B) diffusion C) stream D) substitution
a
21. Verifying that users are who they say they are and that each input arriving at the system came from a trusted source is _________ . A) authenticity B) credibility C) accountability D) integrity
a
22. A __________ is any action that compromises the security of information owned by an organization. A) security attack B) security service C) security alert D) security mechanism
a
27. A(n) __________ is a potential for violation of security, which exists when there is a circumstance, capability, action or event that could breach security and cause harm. A) threat B) attack C) risk D) attack vector
a
4. Restoring the plaintext from the ciphertext is __________ . A) deciphering B) transposition C) steganography D) encryption
a
47. A __________ attack involves trying every possible key until an intelligible translation of the ciphertext is obtained. A) brute-force B) Caesar attack C) ciphertext only D) chosen plaintext
a
5. A __________ attack involves trying every possible key until an intelligible translation of the ciphertext is obtained. A) brute-force B) Caesar attack C) ciphertext only D) chosen plaintext
a
50. The __________ attack is the easiest to defend against because the opponent has the least amount of information to work with. A) ciphertext-only B) chosen ciphertext C) known plaintext D) chosen plaintext
a
53. A technique referred to as a __________ is a mapping achieved by performing some sort of permutation on the plaintext letters. A) transposition cipher B) polyalphabetic cipher C) Caesar cipher D) monoalphabetic cipher
a
54. The methods of __________ conceal the existence of the message in a graphic image. A) steganography B) decryptology C) cryptology D) Cryptography
a
56. The Feistel cipher structure, based on Shannon's proposal of 1945, dates back over a quarter of a century and is the structure used by many significant symmetric block ciphers currently in use. A) True B) False
a
60. Greater complexity in the subkey generation algorithm should lead to greater difficulty of cryptanalysis. A) True B) False
a
61. A prime concern with DES has been its vulnerability to brute-force attack because of its relatively short key length. A) True B) False
a
63. DES exhibits the classic __________ block cipher structure, which consists of a number of identical rounds of processing. A) Feistel B) SAC C) Shannon D) Rendell
a
64. A sequence of plaintext elements is replaced by a __________ of that sequence which means that no elements are added, deleted or replaced in the sequence, but rather the order in which the elements appear in the sequence is changed. A) permutation B) diffusion C) stream D) substitution
a
1. __________ techniques map plaintext elements (characters, bits) into ciphertext elements. A) Transposition B) Substitution C) Traditional D) Symmetric
b
10. The __________ was used as the standard field system by the British Army in World War I and was used by the U.S. Army and other Allied forces during World War II. A) Caesar cipher B) Playfair cipher C) Hill cipher D) Rail Fence cipher
b
