Cryptography and Network Security Principles and Practice, Global Edition, 7th Edition William Stall

Type:

Test Bank

Resource:

Cryptography and Network Security Principles and Practice

Edition:

7th Edition

Author(s):

William Stallings

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 1: COMPUTER AND NETWORK SECURITY CONCEPTS

TRUE OR FALSE 1.

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T F T T F T T F T F T T T F T

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C B B A B A B A B D B D A C B

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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security mechanism active computer security availability encipherment Family Educational Rights and Privacy Act (FERPA) integrity passive attack tree data origin access control Nonrepudiation software attack Notarization

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 1: COMPUTER AND NETWORK SECURITY CONCEPTS TRUE OR FALSE T

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1. The OSI security architecture provides a systematic framework for defining security attacks, mechanisms, and services.

T

F

2. Security attacks are classified as either passive or aggressive.

T

F

3. Authentication protocols and encryption algorithms are examples of security mechanisms.

T

F

4. The more critical a component or service, the higher the level of required availability.

T

F

5. Thanks to years of research and development, it is now possible to develop security design and implementation techniques that systematically exclude security flaws and prevent all unauthorized actions.

T

F

6. The field of network and Internet security consists of measures to deter, prevent, detect and correct security violations that involve the transmission of information.

T

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7. Patient allergy information is an example of an asset with a high requirement for integrity.

T

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8. The OSI security architecture was not developed as an international standard, therefore causing an obstacle for computer and communication vendors when developing security features.

T

F

9. Data origin authentication does not provide protection against the modification of data units.

T

F

10. The emphasis in dealing with active attacks is on prevention rather than detection.

T

F

11. The connection-oriented integrity service addresses both message stream modification and denial of service.

T

F

12. All the techniques for providing security have two components: a security-related transformation on the information to be sent and some secret information shared by the two principals.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

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13. An attack tree is a branching hierarchical data structure that represents a set of potential techniques for exploiting security vulnerabilities.

T

F

14. The data integrity service inserts bits into gaps in a data stream to frustrate traffic analysis attempts.

T

F

15. Symmetric encryption is used to conceal the contents of blocks or streams of data of any size, including messages, files, encryption keys, and passwords.

MULTIPLE CHOICE 1. __________ 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

2. 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

3. __________ 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

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

4. _________ refers to the use of multiple, overlapping protection approaches addressing the people, technology, and operational aspects of information systems.

A) Layering

B) Modularity

C) Encapsulation

D) Open design

5. A loss of __________ is the unauthorized disclosure of information.

A) authenticity

B) confidentiality

C) reliability

D) integrity

6. 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

7. A _________ level breach of security could cause a significant degradation in mission capability to an extent and duration that the organization is able to perform its primary functions, but the effectiveness of the functions is significantly reduced.

A) catastrophic

B) moderate

C) low

D) high

8. 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

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

9. A __________ takes place when one entity pretends to be a different entity.

A) replay

B) masquerade

C) service denial

D) passive attack

10. __________ is the protection of transmitted data from passive attacks.

A) Access control

B) Data control

C) Nonrepudiation

D) Confidentiality

11. 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

12. __________ threats exploit service flaws in computers to inhibit use by legitimate users.

A) Information access

B) Reliability

C) Passive

D) Service

13. 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

14. 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

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

15. 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

SHORT ANSWER 1. A ___________ is any process, or a device incorporating such a process, that is designed to detect, prevent, or recover from a security attack. Examples are encryption algorithms, digital signatures and authentication protocols.

2. An __________ attack attempts to alter system resources or affect their operation.

3. "The protection afforded to an automated information system in order to attain the applicable objectives of preserving the integrity, availability and confidentiality of information system resources" is the definition of _________ .

4. A loss of __________ is the disruption of access to or use of information or an information system.

5. Irreversible __________ mechanisms include hash algorithms and message authentication codes, which are used in digital signature and message authentication applications.

6. In the United States, the release of student grade information is regulated by the __________ .

7. A loss of _________ is the unauthorized modification or destruction of information.

8. A _________ attack attempts to learn or make use of information from the system but does not affect system resources.

9. An _________ is a branching, hierarchical data structure that represents a set of potential techniques for exploiting security vulnerabilities.

10. Two specific authentication services defined in X.800 are peer entity authentication and _________ authentication.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. In the context of network security, ___________ is the ability to limit and control the access to host systems and applications via communications links.

12. __________ prevents either sender or receiver from denying a transmitted message. Thus, when a message is sent, the receiver can prove that the alleged sender in fact sent the message and when a message is received, the sender can prove that the alleged receiver in fact received the message.

13. Viruses and worms are two examples of _________ attacks. Such attacks can be introduced into a system by means of a disk that contains the unwanted logic concealed in otherwise useful software. They can also be inserted into a system across a network.

14. An __________ is an assault on system security that derives from an intelligent act that is a deliberate attempt to evade security services and violate the security policy of a system.

15. __________ is the use of a trusted third party to assure certain properties of a data exchange.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 2: INTRODUCTION TO NUMBER THEORY

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T F F T T T F T T T T F T F F

MULTIPLE CHOICE 1.

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A A A C C D B B C A B A D C A

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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residue Euclidean modulus Euler’s Fermat’s relatively prime Euler’s totient Chinese Remainder prime Diffie-Hellman key exchange logarithm one (1) prime AKS Congruences

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 2: INTRODUCTION TO NUMBER THEORY TRUE OR FALSE T

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1. The algorithm credited to Euclid for easily finding the greatest common divisor of two integers has broad significance in cryptography.

T

F

2. Unlike ordinary addition, there is not an additive inverse to each integer in modular arithmetic.

T

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3. The scheme where you can find the greatest common divisor of two integers by repetitive application of the division algorithm is known as the Brady algorithm.

T

F

4. Two integers a and b are said to be congruent modulo n, if (a mod n) = (b mod n).

T

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5. Basic concepts from number theory that are needed for understanding finite fields include divisibility, the Euclidian algorithm, and modular arithmetic.

T

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6. If b|a we say that b is a divisor of a.

T

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7. The notation a|b is commonly used to mean b divides a.

T

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8. The rules for ordinary arithmetic involving addition, subtraction, and multiplication carry over into modular arithmetic.

T

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9. Two theorems that play important roles in public-key cryptography are Fermat’s theorem and Euler’s theorem.

T

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10. One of the useful features of the Chinese remainder theorem is that it provides a way to manipulate potentially very large numbers mod M in terms of tuples of smaller numbers.

T

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11. For many cryptographic algorithms, it is necessary to select one or more very large prime numbers.

T

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12. The Chinese Remainder Theorem is believed to have been discovered by the Chinese mathematician Agrawal in 100 A.D.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

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13. The primitive roots for the prime number 19 are 2, 3, 10, 13, 14 and 15.

T

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14. The first assertion of the CRT, concerning arithmetic operations, follows from the rules for modular arithmetic.

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15. All integers have primitive roots. .

MULTIPLE CHOICE 1. An integer p >1 is a _________ number if and only if its only divisors are + 1 and + p.

A) prime

B) composite

C) indexed

D) positive

2. Two integers are __________ if their only common positive integer factor is 1.

A) relatively prime C) polynomials

B) congruent modulo D) residual

3. The __________ of two numbers is the largest integer that divides both numbers.

A) greatest common divisor

B) prime polynomial

C) lowest common divisor

D) integral divisor

4. An important quantity in number theory referred to as __________ is defined as the number of positive integers less than n and relatively prime to n.

A) CRT C) Euler’s totient function

B) Miller-Rabin D) Fermat’s theorem

5. Prime numbers play a __________ role in number theory.

.

A) minor

B) nonessential

C) critical

D) abbreviated

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. If p is prime and a is a positive integer, then ap = a(mod p) is an alternative form of _________ theorem.

A) Rijndael’s

B) Vignere’s

C) Euler’s

D) Fermat’s

7. Two numbers are relatively prime if they have ________ prime factors in common.

A) some C) multiple

B) no D) all

8. For given integers a and b, the extended __________ algorithm not only calculates the greatest common divisor d but also two additional integers x and y.

A) modular C) associative

B) Euclidean D) cyclic

9. The procedure TEST takes a candidate integer n as input and returns the result __________ if n is definitely not a prime.

A) discrete C) inconclusive

B) composite D) primitive

10. If a number is the highest possible exponent to which a number can belong, it is referred to as a _________ of n.

.

A) primitive root

B) composite

C) discrete logarithm

D) bijection

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. For any integer b and a primitive root a of prime number p we can find a unique exponent i. This exponent i is referred to as the ___________ .

A) order C) bijection

B) discrete logarithm D) primitive root

12. Discrete logarithms are fundamental to a number of public-key algorithms including __________ key exchange and the DSA. A) Diffie-Hellman

B) Rijndael-Fadiman

C) Fermat-Euler

D) Miller-Rabin

13. The congruence relation is used to define __________ .

A) finite groups C) lowest common divisor

B) greatest common divisor D) residue classes

14. As a _________ relation, mod expresses that two arguments have the same remainder with respect to a given modulus.

A) finite

B) monic

C) congruence

D) cyclic

15. A one-to-one correspondence is called __________.

.

A) a bijection

B) an inclusive

C) an index

D) a composite

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. The remainder r in the division algorithm is often referred to as a __________ .

2. One of the basic techniques of number theory is the __________ algorithm which is a simple procedure for determining the greatest common divisor of two positive integers.

3. If a is an integer and n is a positive integer, we define a mod n to be the remainder when a is divided by n. The integer n is called the __________ .

4. Two theorems that play important roles in public-key cryptography are Fermat's theorem and __________ theorem.

5.

__________ theorem states the following: If p is prime and a is a positive integer not divisible by p, then ap-1 = 1(mod p).

6.

Two numbers are __________ if their greatest common divisor is 1.

7. The number of positive integers less than n and relatively prime to n is referred to as __________ function.

8. The __________ theorem states that it is possible to reconstruct integers in a certain range from their residues modulo a set of pairwise relatively prime moduli.

9. Two integers are relatively _________ if and only if their only common positive integer factor is 1.

10. Discrete logarithms are fundamental to the digital signature algorithm (DSA) and the _________ algorithm.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. The _________ of a number is defined to be the power to which some positive base (except 1) must be raised in order to equal the number.

12. Two numbers are relatively prime if their greatest common divisor is ______.

13. An integer p > 1 is a __________ number if and only if its only divisors are + 1 and + p.

14. Although it does not appear to be as efficient as the Miller-Rabin algorithm, in 2002 a relatively simple deterministic algorithm that efficiently determines whether a given large number is a prime was developed. This algorithm is known as the _________ algorithm 15. ____________ have the following properties: 1. a = b (mod n) if n| (a - b) 2. a = b (mod n) implies b = a (mod n) 3. a = b (mod n) and b = c (mod n) imply a = c (mod n)

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 3: CLASSICAL ENCRYPTION TECHNIQUES

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MULTIPLE CHOICE 1.

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B B B A A C B D B B A C C A A

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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Symmetric Steganography computationally secure brute-force the number of keys used transposition Vigenère block unconditionally Caesar Playfair one-time pad rail fence Data Encryption Standard (DES) rotor machines

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 3: CLASSICAL ENCRYPTION TECHNIQUES TRUE OR FALSE T

F

1. Symmetric encryption remains by far the most widely used of the two types of encryption.

T

F

2. Rotor machines are sophisticated precomputer hardware devices that use substitution techniques.

T

F

3. Symmetric encryption is a form of cryptosystem in which encryption and decryption are performed using different keys. It is also known as non-conventional encryption.

T

F

4. With the use of symmetric encryption, the principal security problem is maintaining the secrecy of the key.

T

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5. The process of converting from plaintext to ciphertext is known as deciphering or decryption.

T

F

6. The algorithm will produce a different output depending on the specific secret key being used at the time. The exact substitutions and transformations performed by the algorithm depend on the key.

T

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7. When using symmetric encryption it is very important to keep the algorithm secret.

T

F

8. On average, half of all possible keys must be tried to achieve success with a brute-force attack.

T

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9. Ciphertext generated using a computationally secure encryption scheme is impossible for an opponent to decrypt simply because the required information is not there.

T

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10. Monoalphabetic ciphers are easy to break because they reflect the frequency data of the original alphabet.

T

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11. As with Playfair, the strength of the Hill cipher is that it completely hides single letter frequencies.

T

F

12. A scheme known as a one-time pad is unbreakable because it produces random output that bears no statistical relationship to the plaintext.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

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13. The one-time pad has unlimited utility and is useful primarily for high-bandwidth channels requiring low security.

T

F

14. The most widely used cipher is the Data Encryption Standard.

T

F

15. Steganography renders the message unintelligible to outsiders by various transformations of the text.

MULTIPLE CHOICE 1. __________ techniques map plaintext elements (characters, bits) into ciphertext elements.

A) Transposition

B) Substitution

C) Traditional

D) Symmetric

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

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) ciphertext, plaintext

D) encryption, decryption

4. Restoring the plaintext from the ciphertext is __________ .

.

A) deciphering

B) transposition

C) steganography

D) encryption

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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

6. Techniques used for deciphering a message without any knowledge of the enciphering details is ___________ .

A) blind deciphering

B) steganography

C) cryptanalysis

D) transposition

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

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

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

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

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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

12. _________ refer to common two-letter combinations in the English language.

A) Streamings

B) Transpositions

C) Digrams

D) Polyalphabetic ciphers

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

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

15. The methods of __________ conceal the existence of the message in a graphic image.

A) steganography

B) decryptology

C) cryptology

D) cryptography

SHORT ANSWER 1. __________ encryption is a form of cryptosystem in which encryption and decryption are performed using the same key.

2. A technique for hiding a secret message within a larger document or picture in such a way that others cannot discern the presence or contents of the hidden message is __________ . .

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

3. An encryption scheme is said to be __________ if the cost of breaking the cipher exceeds the value of the encrypted information and the time required to break the cipher exceeds the useful lifetime of the information.

4. The two types of attack on an encryption algorithm are cryptanalysis, based on properties of the encryption algorithm, and _________ which involves trying all possible keys.

5. Cryptographic systems are characterized along three independent dimensions: the type of operations used for transforming plaintext to ciphertext; the way in which the plaintext is processed; and __________ .

6. All encryption algorithms are based on two general principles: substitution and ____________ .

7. One of the simplest and best known polyalphabetic ciphers is _________ cipher. In this scheme, the set of related monoalphabetic substitution rules consists of the 26 Caesar ciphers with shifts of 0 through 25. Each cipher is denoted by a key letter which is the ciphertext letter that substitutes for the plaintext letter a.

8. A __________ cipher processes the input one block of elements at a time, producing an output block for each input block, whereas a stream cipher processes the input elements continuously, producing output one element at a time.

9. An encryption scheme is __________ secure if the ciphertext generated by the scheme does not contain enough information to determine uniquely the corresponding plaintext, no matter how much ciphertext is available.

10. The earliest known, and simplest use, of a substitution cipher was called the __________ cipher and involved replacing each letter of the alphabet with the letter standing three places further down the alphabet.

11. The best known multiple letter encryption cipher is the __________ , which treats digrams in the plaintext as single units and translates these units into ciphertext digrams.

12. The task of making large quantities of random keys on a regular basis and distributing a key of equal length to both sender and receiver for every message sent are difficulties of the __________ scheme.

13. The simplest transposition cipher is the _________ technique, in which the plaintext is written down as a sequence of diagonals and then read off as a sequence of rows.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

14. The most widely used cipher ever is the __________ .

15. The __________ consist of a set of independently rotating cylinders through which electrical pulses can flow. Each cylinder has 26 input pins and 26 output pins with internal wiring that connects each input pin to a unique output pin.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 4: BLOCK CIPHERS AND THE DATA ENCRYPTION STANDARD

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F T F T T F F T T T F T F T F

MULTIPLE CHOICE 1.

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A A D B D A D D B D C A C A C

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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block cipher Confusion Feistel diffusion guaranteed avalanche (GA) diffusion Data Encryption Standard (DES) avalanche key size timing bit independence Feistel the number of rounds strict avalanche triple

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 4: BLOCK CIPHERS AND THE DATA ENCRYPTION STANDARD TRUE OR FALSE T

F

1. The vast majority of network based symmetric cryptographic applications make use of stream ciphers.

T

F

2. 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.

T

F

3. DES uses a 56-bit block and a 64-bit key.

T

F

4. If the bit-stream generator is a key-controlled algorithm the two users only need to share the generating key and then each can produce the keystream.

T

F

5. A problem with the ideal block cipher using a small block size is that it is vulnerable to a statistical analysis of the plaintext.

T

F

6. Confusion seeks to make the statistical relationship between the plaintext and ciphertext as complex as possible in order to thwart attempts to deduce the key.

T

F

7. All other things being equal, smaller block sizes mean greater security.

T

F

8. Greater complexity in the subkey generation algorithm should lead to greater difficulty of cryptanalysis.

T

F

9. Fast software encryption/decryption and ease of analysis are two considerations in the design of a Feistel cipher.

T

F

10. A prime concern with DES has been its vulnerability to brute-force attack because of its relatively short key length.

T

F

11. One criteria for an S-box is: "If two inputs to an S-box differ in exactly one bit, the outputs must also differ in exactly one bit. “

T

F

12. The heart of a Feistel block cipher is the function F, which relies on the use of S-boxes.

T

F

13. The strict avalanche criterion and the bit independence criterion appear to weaken the effectiveness of the confusion function.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. An advantage of key-dependent S-boxes is that because they are not fixed, it is impossible to analyze the S-boxes ahead of time to look for weaknesses.

T

F

15. The key schedule algorithm is more popular and has received more attention than S-box design.

MULTIPLE CHOICE 1. DES exhibits the classic __________ block cipher structure, which consists of a number of identical rounds of processing.

A) Feistel C) Shannon

B) SAC D) Rendell

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

3. A __________ cipher is one that encrypts a digital data stream one bit or one byte at a time.

A) product C) key

B) block D) stream

4. The vast majority of network-based symmetric cryptographic applications make use of ________ ciphers.

A) linear

B) block

C) permutation

D) stream

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

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. __________ is when each plaintext element or group of elements is uniquely replaced by a corresponding ciphertext element or group of elements.

A) Substitution

B) Diffusion

C) Streaming

D) Permutation

7. Key sizes of __________ or less are now considered to be inadequate.

A) 128 bits C) 16 bits 8.

B) 32 bits D) 64 bits

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

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 C) Product Cipher

B) Data Encryption Standard D) Substitution Key

10. The greater the number of rounds, the __________ it is to perform cryptanalysis.

A) easier C) equally difficult

B) less difficult D) harder

11. The function F provides the element of __________ in a Feistel cipher.

.

A) clarification

B) alignment

C) confusion

D) stability

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

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

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

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

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

SHORT ANSWER 1. A _________ is an encryption/decryption scheme in which a block of plaintext is treated as a whole and used to produce a ciphertext block of equal length.

2.

.

__________ seeks to make the relationship between the statistics of the ciphertext and the value of the encryption key as complex as possible so that even if the attacker can get some handle on the statistics of the ciphertext, the way in which the key was used to produce that ciphertext is so complex it is difficult to deduce the key.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

3. Many block ciphers have a __________ structure which consists of a number of identical rounds of processing and in each round a substitution is performed on one half of the data being processed, followed by a permutation that interchanges the two halves.

4. Feistel’s is a practical application of a proposal by Claude Shannon to develop a product cipher that alternates confusion and ________ functions.

5. The __________ criterion is defined as: "An S-box satisfies GA of order y if, for a 1-bit input change, at least y output bits change."

6. In ___________ the statistical structure of the plaintext is dissipated into longrange statistics of the ciphertext. This is achieved by having each plaintext digit affect the value of many ciphertext digits.

7. The most widely used encryption scheme is based on the __________ adopted in 1977 by the National Bureau of Standards as Federal Information Processing Standard 46.

8. A change in one bit of the plaintext or one bit of the key should produce a change in many bits of the ciphertext. This is referred to as the __________ effect.

9. Two areas of concern regarding the level of security provided by DES are the nature of the algorithm and the __________ .

10. A _________ attack exploits the fact that an encryption or decryption algorithm often takes slightly different amounts of time on different inputs.

11. The __________ criterion states that output bits j and k should change independently when any single input bit i is inverted for all i, j and k.

12. The ________ cipher structure, which dates back over a quarter century and which, in turn, is based on Shannon’s proposal of 1945, is the structure used by many significant symmetric block ciphers currently in use.

13. The cryptographic strength of a Feistel cipher derives from three aspects of the design: the function F, the key schedule algorithm, and __________ .

14. The __________ criterion states that any output bit j of an S-box should change with probability 1/2 when any single input bit i is inverted for all i,j.

15. Two alternatives to DES are AES and _________ DES.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 5: FINITE FIELDS

TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F F T F T F T F T F T T F T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

D A A B A A C B A C B D D C B

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

residue Euclidean modulus monic integral Advanced Encryption Standard (AES) integral Galois prime constant irreducible greatest common divisor prime generator root

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 5: FINITE FIELDS TRUE OR FALSE T

F

1. Finite fields play a crucial role in many cryptographic algorithms.

T

F

2. Rings are a subset of a larger class of algebraic structures called fields.

T

F

3. Groups are defined by a complex set of properties and are difficult to understand.

T

F

4. Finite fields are a subset of fields, consisting of those fields with a finite number of elements.

T

F

5. Cryptographic algorithms do not rely on properties of finite fields.

T

F

6. A more important class of finite fields, for cryptography, comprises those with 2n elements depicted as fields of the form GF(2n).

T

F

7. The Advanced Encryption Standard uses infinite fields.

T

F

8. Groups, rings, and fields are the fundamental elements of a branch of mathematics known as abstract algebra.

T

F

9. A cyclic group is always commutative and may be finite or infinite.

T

F

10. A field is a set in which we can do addition, subtraction, multiplication and division without leaving the set.

T

F

11. It is easy to find the multiplicative inverse of an element in g(p) for large values of p by constructing a multiplication table, however for small values of p this approach is not practical.

T

F

12. Polynomial arithmetic includes the operations of addition, subtraction and multiplication.

T

F

13. If we attempt to perform polynomial division over a coefficient set that is not a field, we find that division is not always defined.

T

F

14. The Euclidean algorithm cannot be adapted to find the multiplicative inverse of a polynomial.

T

F

15. The elements of GF(2n) can be defined as the set of all polynomials

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

of degree n – 1 or less with binary coefficients.

MULTIPLE CHOICE 1. The Advanced Encryption Standard and elliptic curve cryptography rely heavily on properties of _________ .

A) order

B) polynomials

C) groups

D) finite fields

2. Two integers are __________ if their only common positive integer factor is 1.

A) relatively prime C) polynomials

B) congruent modulo D) residual

3. The ________ of the group is equal to the number of elements in the group.

A) order C) modulus

B) generator D) integral divisor

4. A ring is said to be _________ if it satisfies the condition ab = ba for all a, b in R. A) cyclic

B) commutative

C) abelian

D) infinite

5. A _________ is a set of elements in which we can do addition, subtraction, multiplication, and division without leaving the set.

A) field

B) modulus

C) group

D) ring

6. A _________ is a group that has a finite number of elements.

.

A) finite group

B) finite order

C) finite field

D) finite ring

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

7. A ________ group is always abelian and may be finite or infinite.

A) residue

B) commutative

C) cyclic

D) modulus

8. We can adapt the __________ algorithm to compute the greatest common divisor of two polynomials.

A) abelian

B) Euclidean

C) associative

D) cyclic

9. A group is said to be _________ if it satisfies the condition a * b = b * a for all a, b in G. A) abelian

B) infinite

C) cyclic

D) commutative

10. In the context of abstract algebra we are usually not interested in evaluating a polynomial for a particular value of x. To emphasize this point the variable x is sometimes referred to as the __________ .

A) monic

B) constant

C) indeterminate

D) coefficient

11. With the understanding that remainders are allowed, we can say that polynomial division is possible if the coefficient set is a __________ .

A) ring

B) field

C) factor

D) divisor

12. By analogy to integers, an irreducible polynomial is also called a __________ .

A) constant polynomial .

B) monic polynomial

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

C) polynomial ring

D) prime polynomial

13. In ________ algebra we are not limited to ordinary arithmetical operations.

A) finite

B) commutative

C) modulus

D) abstract

14. Examples of _________ are the rational numbers, the real numbers, and the complex numbers.

A) rings

B) orders

C) fields

D) groups

15. The order of a finite field must be of the form pn where p is a prime and n is a __ .

A) identity element C) commutative ring

B) positive integer D) associative

SHORT ANSWER 1. The _________ class [x + 1] consists of all polynomials a(x) that satisfy the quality a(x) mod m(x) = x + 1.

2. One of the basic techniques of number theory is the __________ algorithm which is a simple procedure for determining the greatest common divisor of two polynomials.

3. The mathematician who first studied finite fields was __________ .

4. An nth-degree polynomial is said to be a _________ polynomial if an = 1.

5.

An _________ domain is a commutative ring that obeys the axioms multiplicative identity and no zero divisors.

6. Elliptic curve cryptography and the _________ are two cryptographic algorithms that rely heavily on properties of finite fields. .

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

7. Let S be the set of integers (positive, negative, and 0) under the usual operations of addition and multiplication. S is an __________ domain.

8. GF stands for __________ field in honor of the mathematician who first studied finite fields.

9. Two integers are relatively _________ if their only common positive integer factor is 1.

10. A zero-degree polynomial is called a __________ polynomial and is simply an element of the set of coefficients.

11. A polynomial f(x) over a field F is called __________ if and only if f(x) cannot be expressed as a product of two polynomials, both over F, and both of degree lower than that of f(x).

12. The polynomial c(x) is said to be the __________ of a(x) and b(x) if c(x) divides both a(x) and b(x) and any divisor of a(x) and b(x) is a divisor of c(x).

13. By analogy to integers, an irreducible polynomial is also called a _________ polynomial.

14. A __________ g of a finite field F or order q is an element whose first q - 1 powers generate all the nonzero elements of F. 15. Consider a field F defined by a polynomial f(x). An element b contained in F is called a __________ of the polynomial if f(b) = 0.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 6: ADVANCED ENCRYPTION STANDARD

TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

F T F T T T F T F T F T T F T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

D A B C A D B C B B A B A C A

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

Advanced Encryption Standard (AES) byte substitution Rijndael key length substitutions MixColumns SubBytes MixColumns shift row 44 AddRoundKey InvShiftRows 32-bit prime number irreducible

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 6: ADVANCED ENCRYPTION STANDARD TRUE OR FALSE T

F

1. AES uses a Feistel structure.

T

F

2. At each horizontal point, State is the same for both encryption and decryption.

T

F

3. DES is a block cipher intended to replace AES for commercial applications.

T

F

4. The nonlinearity of the S-box is due to the use of the multiplicative inverse.

T

F

5. Virtually all encryption algorithms, both conventional and publickey, involve arithmetic operations on integers.

T

F

6. Compared to public-key ciphers such as RSA, the structure of AES and most symmetric ciphers is quite complex and cannot be explained as easily as many other cryptographic algorithms.

T

F

7. InvSubBytes is the inverse of ShiftRows.

T

F

8. The ordering of bytes within a matrix is by column.

T

F

9. In the Advanced Encryption Standard the decryption algorithm is identical to the encryption algorithm.

T

F

10. The S-box is designed to be resistant to known cryptanalytic attacks.

T

F

11. As with any block cipher, AES can be used to construct a message authentication code, and for this, only decryption is used.

T

F

12. The inverse add round key transformation is identical to the forward add round key transformation because the XOR operation is its own inverse.

T

F

13. The Rijndael developers designed the expansion key algorithm to be resistant to known cryptanalytic attacks.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. The transformations AddRoundKey and InvMixColumn alter the sequence of bytes in State.

T

F

15. AES can be implemented very efficiently on an 8-bit processor.

MULTIPLE CHOICE 1. The Advanced Encryption Standard was published by the __________ in 2001.

A. ARK

B. FIPS

C. IEEE

D. NIST

2. In Advanced Encryption Standard all operations are performed on __________ bytes.

A. 8-bit

B. 16-bit

C. 32-bit

D. 4-bit

3. The AES cipher begins and ends with a(n) _________ stage because any other stage, applied at the beginning or end, is reversible without knowledge of the key and would add no security.

A. Substitute bytes

B. AddRoundKey

C. MixColumns

D. ShiftRows

4. A __________ is a set in which you can do addition, subtraction, multiplication and division without leaving the set.

A. record

B. standard

C. field

D. block

5. Division requires that each nonzero element have a(n) __________ inverse.

.

A. multiplicative

B. divisional

C. subtraction

D. addition

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. In AES, the arithmetic operations of addition, multiplication and division are performed over the finite field _________ .

A. Zp

B. a/b = a(b-1)

C. GF(2n-1)

D. GF(28)

7. In the AES structure both encryption and decryption ciphers begin with a(n) __________ stage, followed by nine rounds that each include all four stages, followed by a tenth round of three stages.

A. Substitute bytes

B. AddRoundKey

C. MixColumns

D. ShiftRows

8. The final round of both encryption and decryption of the AES structure consists of __________ stages.

A. one

B. two

C. three

D. four

9. The first row of State is not altered; for the second row a 1-byte circular left shift is performed; for the third row a 2-byte circular left shift is performed; and for the fourth row a 3-byte circular left shift is performed. This transformation is called __________ .

A. AddRoundKey

B. ShiftRows

C. MixColumns

D. Substitute bytes

10. In the AddRoundKey transformation the 128 bits of State are bitwise XORed with the _________ of the round key.

.

A. 64 bits

B. 128 bits

C. 256 bits

D. 512 bits

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. The __________ is when a small change in plaintext or key produces a large change in the ciphertext.

A. avalanche effect

B. Rcon

C. key expansion

D. auxiliary exchange

12. The encryption round has the structure: A. ShiftRows, MixColumns, SubBytes, InvMixColumns B. SubBytes, ShiftRows, MixColumns, AddRoundKey C. MixColumns, ShiftRows, SubBytes, AddRoundKey D. InvShiftRows, InvSubBytes, AddRoundKey, InvMixColumns 13. __________ affects the contents of bytes in State but does not alter byte sequence and does not depend on byte sequence to perform its transformation.

A. InvSubBytes

B. ShiftRows

C. SubBytes

D. InvShiftRows

14. In the general structure of the AES encryption process the input to the encryption and decryption algorithms is a single _________ block.

A. 32-bit

B. 64-bit

C. 128-bit

D. 256-bit

15. The cipher consists of N rounds, where the number of rounds depends on the __________ .

.

A. key length

B. output matrix

C. State

D. number of columns

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. The __________ is a block cipher intended to replace DES for commercial applications. It uses a 128-bit block size and a key size of 128, 192, or 256 bits.

2. The four separate functions of the Advanced Encryption Standard are: permutation, arithmetic operations over a finite field, XOR with a key, and __________ .

3. The National Institute of Standards and Technology chose the __________ design as the winning candidate for AES. 4. The cipher consists of N rounds, where the number of rounds depends on the __________ .

5. AES processes the entire data block as a single matrix during each round using __________ and permutation.

6. The first N - 1 rounds consist of four distinct transformation functions: SubBytes, ShiftRows, AddRoundKey, and __________ .

7. The forward substitute byte transformation, called _________ , is a simple table lookup.

8. The _________ transformation operates on each column individually. Each byte of a column is mapped into a new value that is a function of all four bytes in that column.

9. The mix column transformation combined with the __________ transformation ensures that after a few rounds all output bits depend on all input bits.

10. The AES key expansion algorithm takes as input a four-word (16-byte) key and produces a linear array of __________ words (176 bytes).

11. The standard decryption round has the structure InvShiftRows, InvSubBytes, __________, InvMixColumns.

12. ___________ affects the sequence of bytes in State but does not alter byte contents and does not depend on byte contents to perform its transformation.

13. A more efficient implementation can be achieved for a 32-bit processor if operations are defined on _________ words. .

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

14. An example of a finite field is the set Zp consisting of all the integers {0, 1, . . . , p - 1}, where p is a __________ and in which arithmetic is carried out modulo p.

15. A polynomial m(x) is called __________ if and only if m(x) cannot be expressed as a product of two polynomials, both of degree lower than that of m(x).

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 7: BLOCK CIPHER OPERATION

TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

F T T F F T F F T F T T F T T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

B D A D B C C B D C B C B D B

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

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11.

12.

13.

14.

15.

.

Multiple encryption electronic codebook mode (ECB) mode of operation output feedback mode (OFB) triple DES Cipher Block Chaining (CBC) electronic codebook format-preserving encryption (FPE) Counter (CTR) Cipher Feedback (CFB) nonce stream Counter ciphertext-stealing P1619

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 7: BLOCK CIPHER OPERATION TRUE OR FALSE T

F

1. Once the plaintext is converted to ciphertext using the encryption algorithm the plaintext is then used as input and the algorithm is applied again.

T

F

2. There are no practical cryptanalytic attacks on 3DES.

T

F

3. A mode of operation is a technique for enhancing the effect of a cryptographic algorithm or adapting the algorithm for an application.

T

F

4. The XTS-AES standard describes a method of decryption for data stored in sector-based devices where the threat model includes possible access to stored data by the adversary.

T

F

5. S-AES is the most widely used multiple encryption scheme.

T

F

6. Given the potential vulnerability of DES to a brute-force attack, an alternative has been found.

T

F

7. A number of Internet based applications have adopted two-key 3DES, including PGP and S/MIME.

T

F

8. The sender is the only one who needs to know an initialization vector.

T

F

9. A typical application of Output Feedback mode is stream oriented transmission over noisy channel, such as satellite communication.

T

F

10. Cipher Feedback (CFB) is used for the secure transmission of single values.

T

F

11. Format-preserving encryption refers to any encryption technique that takes a plaintext in a given format and produces a ciphertext in the same format.

T

F

12. It is possible to convert a block cipher into a stream cipher using cipher feedback, output feedback and counter modes.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

13. Cipher Feedback Mode conforms to the typical construction of a stream cipher.

T

F

14. OFB mode requires an initialization vector that must be unique to each execution of the encryption operation.

T

F

15. The XTS-AES mode is based on the concept of a tweakable block cipher.

MULTIPLE CHOICE 1. In the first instance of multiple encryption plaintext is converted to __________ using the encryption algorithm.

A. block cipher

B. ciphertext

C. S-AES mode

D. Triple DES

2. Triple DES makes use of __________ stages of the DES algorithm, using a total of two or three distinct keys.

A. nine

B. six

C. twelve

D. three

3. Another important mode, XTS-AES, has been standardized by the __________ Security in Storage Working Group.

A. IEEE

B. ISO

C. NIST

D. ITIL

4. The _________ and _________ block cipher modes of operation are used for authentication.

.

A. OFB, CTR

B. ECB, CBC

C. CFB, OFB

D. CBC, CFB

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. __________ modes of operation have been standardized by NIST for use with symmetric block ciphers such as DES and AES. A. Three

B. Five

C. Nine

D. Seven

6. The output of the encryption function is fed back to the shift register in Output Feedback mode, whereas in ___________ the ciphertext unit is fed back to the shift register.

A. Cipher Block Chaining mode

B. Electronic Codebook mode

C. Cipher Feedback mode

D. Counter mode

7. The simplest form of multiple encryption has __________ encryption stages and __________ keys.

A. four, two

B. two, three

C. two, two

D. three, two

8. The __________ algorithm will work against any block encryption cipher and does not depend on any particular property of DES. A. cipher block chaining

B. meet-in-the-middle attack

C. counter mode attack

D. ciphertext stealing

9. The __________ method is ideal for a short amount of data and is the appropriate mode to use if you want to transmit a DES or AES key securely.

.

A. cipher feedback mode

B. counter mode

C. output feedback mode

D. electronic codebook mode

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

10. _________ mode is similar to Cipher Feedback, except that the input to the encryption algorithm is the preceding DES output.

A. Cipher Feedback

B. Counter

C. Output Feedback

D. Cipher Block Chaining

11. “Each block of plaintext is XORed with an encrypted counter. The counter is incremented for each subsequent block", is a description of ___________ mode.

A. Cipher Block Chaining

B. Counter

C. Cipher Feedback

D. Electronic Codebook

12. The __________ mode operates on full blocks of plaintext and ciphertext, as opposed to an s-bit subset.

A. CBC

B. ECB

C. OFB

D. CFB

13. A finite set of two or more symbols is called a(n) ___________ .

A. character

B. alphabet

C. radix

D. character string

14. __________ mode is suitable for parallel operation. Because there is no chaining, multiple blocks can be encrypted or decrypted simultaneously.

Unlike CTR mode, this mode includes a nonce as well as a counter.

A. OFB

B. S-AES

C. 3DES

D. XTS-AES

15. Both __________ produce output that is independent of both the plaintext and the ciphertext. This makes them natural candidates for stream ciphers that encrypt plaintext by XOR one full block at a time.

.

A. CBC and ECB

B. OFB and CTR

C. ECB and OFB

D. CTR and CBC

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. The__________ is a technique in which an encryption algorithm is used multiple times.

2. The most significant characteristic of __________ is that if the same b-bit block of plaintext appears more than once in the message, it always produces the same ciphertext.

3. A __________ is a technique for enhancing the effect of a cryptographic algorithm or adapting the algorithm for an application, such as applying a block cipher to a sequence of data blocks or a data stream.

4. Five modes of operation have been standardized by NIST for use with symmetric block ciphers such as DES and AES: electronic codebook mode, cipher block chaining mode, cipher feedback mode, __________, and counter mode.

5. One of the most widely used multiple-encryption schemes is __________ .

6. "The input to the encryption algorithm is the XOR of the next 64 bits of plaintext and the preceding 64 bits of ciphertext" is a description of __________ mode.

7. The simplest mode of operation is the ___________ mode, in which plaintext is handled one block at a time and each block of plaintext is encrypted using the same key.

8. __________ refers to any encryption technique that takes a plaintext in a given format and produces a ciphertext in the same format.

9. The __________ block cipher mode of operation is a general purpose block oriented transmission useful for high speed requirements.

10. "Input is processed s bits at a time. Preceding ciphertext is used as input to the encryption algorithm to produce pseudorandom output, which is XORed with plaintext to produce next unit of ciphertext", is a description of the _________ mode of operation.

11. The _________ must be a data block that is unique to each execution of the encryption operation and may be a counter, a timestamp, or a message number.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

12. A __________ cipher can operate in real time and eliminates the need to pad a message to be an integral number of blocks.

13. Hardware efficiency, software efficiency, preprocessing, random access, provable security, and simplicity are all advantages of __________ mode.

14. The plaintext of a sector or data unit is organized in to blocks of 128 bits. For encryption and decryption, each block is treated independently. The only exception occurs when the last block has less than 128 bits. In that case the last two blocks are encrypted/decrypted using a ___________ technique instead of padding.

15. The __________ standard describes a method of encryption for data stored in sector-based devices where the threat model includes possible access to stored data by the adversary. Some characteristics of this standard include: the ciphertext is freely available for an attacker, the data layout is not changed on the storage medium and in transit, and the same plaintext is encrypted to different ciphertexts at different locations.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 8: RANDOM BIT GENERATION AND STREAM CIPHERS TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T T F T T F T F T T T F T F T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

C A B D A A A D B B D B A B B

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

stream cipher pseudorandom function (PRF) independence RC4 randomness pseudorandom entropy source pseudorandom number generator (PRNG) runs backward Purpose-built keystream RC4 Linux prime

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 8: RANDOM BIT GENERATION AND STREAM CIPHERS TRUE OR FALSE T

F

1. The principle requirement of random or pseudorandom number generation is that the generated number stream be unpredictable.

T

F

2. Random numbers play an important role in the use of encryption for various network security applications.

T

F

3. There are well-defined tests for determining uniform distribution and independence to validate that a sequence of numbers is random.

T

F

4. With true random sequences each number is statistically independent of other numbers in the sequence and therefore unpredictable.

T

F

5. The true random number generator may simply involve conversion of an analog source to a binary output.

T

F

6. Examples of a pseudorandom function are decryption keys and nonces.

T

F

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

F

8. The purpose of the Maurer's universal statistical test is to determine whether the number of ones and zeros in a sequence are approximately the same as would be expected for a truly random sequence.

T

F

9. The seed that serves as input to the PRNG must be secure for cryptographic applications.

T

F

10. Three broad categories of cryptographic algorithms are commonly used to create PRNGs: symmetric block ciphers, asymmetric ciphers, and hash functions and message authentication codes.

T

F

11. A widely used technique for pseudorandom number generation is an algorithm known as the linear congruential method.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

12. A cryptographically secure pseudorandom bit generator is defined as one that passes the least significant bit test.

T

F

13. The security of Blum, Blum, Shub is based on the difficulty of factoring n.

T

F

14. The stream cipher is similar to the one-time pad with a difference being that a one-time pad uses a pseudorandom number stream and a stream cipher uses a genuine random number stream.

T

F

15. The longer the keyword the more difficult the cryptanalysis.

MULTIPLE CHOICE 1. A secret key for symmetric encryption that is generated for use for a short period of time is called a _________ .

A. strategic key

B. sequence key

C. session key

D. stream key

2. A __________ is used to produce a pseudorandom string of bits of some fixed length.

A. PRF

B. PRNG

C. OFB PRNG

D. TRNG

3. A source that is effectively random is referred to as __________ .

A. an open source

B. an entropy source

C. a keystream

D. a seed

4. A __________ takes as input a source that is effectively random.

.

A. PRF

B. BBS

C. PRNG

D. TRNG

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. A pseudorandom number generator takes as input a fixed value called the __________ and produces a sequence of output bits using a deterministic algorithm.

A. seed

B. fixed skew

C. entropy source

D. keystream

6. The best that can be done to determine if a PRNG generates numbers that have the characteristic of randomness is on the basis of multiple tests. These tests should seek to establish uniformity, scalability, and __________ .

A. consistency

B. authentication

C. frequency

D. sequencing

7. The __________ test is the most basic test of randomness and must be included in any test suite.

A. frequency

B. runs

C. unpredictability

D. Maurer

8. The Blum, Blum, Shub generator is referred to as a ____________ .

A. TRNG

B. OFB PRNG

C. QRN

D. CSPRBG

9. Two approaches that use a block cipher to build a PNRG and have gained widespread acceptance are: A. CTR mode and CFB mode

B. CTR mode and OFB mode

C. CBC mode and CFB mode

D. OFB mode and ECB mode

10. A __________ uses a nondeterministic source to produce randomness.

.

A. CSPRBG

B. TRNG

C. PRNG

D. BBS

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. __________ is an open source project for creating truly random numbers using inexpensive cameras, open source code, and inexpensive hardware.

A. LavaRnd

B. Blum, Blum, Shub

C. Maurer’s statistics

D. Entropy

12. Various methods of modifying a bit stream to reduce or eliminate a bias have been developed. These are referred to as ___________ algorithms.

A. backward

B. deskewing

C. forward

D. keystream

13. The Linux operating system uses _________ entropy sources for generating random numbers.

A. four

B. three

C. one

D. two

14. In key distribution and reciprocal authentication schemes two communicating parties cooperate by exchanging messages to distribute keys and/or authenticate each other. In many cases ___________ are used for handshaking to prevent replay attacks.

A. session keys

B. nonces

C. RC4s

D. entropies

15. The distribution of bits in a random number sequence should be ___________ , therefore the frequency of occurrence of ones and zeros should be approximately equal.

.

A. independent

B. uniform

C. reversed

D. streamed

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. A __________ is a symmetric encryption algorithm in which ciphertext output is produced bit-by-bit or byte-by-byte from a stream of plaintext input.

2. Typically the __________ takes as input a seed plus some context specific values such as a user ID or an application ID. 3. Two criteria used to validate that a sequence of numbers is random are uniform distribution and __________ .

4. The most important and widely used stream cipher is __________ .

5. Two distinct requirements for a sequence of random numbers are unpredictability and __________ .

6. If the algorithm is good the resulting sequences will pass many reasonable tests of randomness. These numbers are referred to as ___________ numbers.

7. The __________ is drawn from the physical environment of the computer and could include things such as keystroke timing patterns, disk electrical activity, mouse movements, and instantaneous values of the system clock.

8. An algorithm that is used to produce an open-ended sequence of bits is referred to as a ___________ .

9. The purpose of the __________ test is to determine whether the number of runs of ones and zeros of various lengths is as expected for a random sequence.

10. A stream of pseudorandom numbers should exhibit two forms of unpredictability: forward and __________ .

11. __________ algorithms are designed specifically and solely for the purpose of generating pseudorandom bit streams.

12. In a stream cipher structure a key is input to a pseudorandom bit generator that produces a stream of 8-bit numbers that are apparently random. The output of the generator, called a ___________ , is combined one byte at a time with the plaintext stream using the bitwise exclusive-OR operation.

13. __________ is a stream cipher designed in 1987 by Ron Rivest for RSA Security.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

14. Operating systems typically provide a built-in mechanism for generating random numbers. For example, __________ uses mouse and keyboard activity, disk I/O operations, and specific interrupts.

15. A fundamental requirement of the RSA public-key encryption scheme is the ability to generate _________ numbers.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 12: MESSAGE AUTHENTICATION CODES TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F T F T F T T F T F T F T T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

C C B B D C D B B A D C C C B

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

message authentication traffic analysis message authentication code (MAC) fixed length sequence modification message encryption cryptographic checksum bit length cryptanalysis data authentication Authenticated encryption (AE) Wired Equivalent Privacy (WEP) Counter with Cipher Block Chaining-Message Authentication Code (CCM) pseudorandom number generators (PRNGs) MAC

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 12: MESSAGE AUTHENTICATION CODES TRUE OR FALSE T

F

1. Message authentication is a mechanism or service used to verify the integrity of a message.

T

F

2. The order in which the frame check sequence and encryption functions are performed is not critical for authentication.

T

F

3. The MAC does not provide a digital signature because both sender and receiver share the same key.

T

F

4. A recipient in possession of the secret key cannot generate an authentication code to verify the integrity of the message.

T

F

5. One means of forming a MAC is to combine a cryptographic hash function in some fashion with a secret key.

T

F

6. A brute-force attack on a MAC is easier than a brute-force attack on a hash function.

T

F

7. Message authentication may also verify sequencing and timeliness.

T

F

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

F

9. Message encryption by itself cannot provide a measure of authentication.

T

F

10. If the calculated frame check sequence is equal to the incoming frame check sequence the message is considered authentic.

T

F

11. The straightforward use of public-key encryption provides confidentiality and authentication.

T

F

12. A CTR-based authenticated encryption approach is the most efficient mode of operation for high-speed packet networks.

T

F

13. An important characteristic of the MAC algorithm is that it needs to be reversible.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. As with encryption algorithms and hash functions cryptanalytic attacks on MAC algorithms seek to exploit some property of the algorithm to perform some attack other than an exhaustive search.

T

F

15. To attack MD5, the attacker can choose any set of messages and work on these offline on a dedicated computing facility to find a collision.

MULTIPLE CHOICE 1. _________ encryption provides authentication among those who share the secret key.

A. Message

B. Asymmetric

C. Symmetric

D. Authenticated

2. The __________ mode of operation is designed to be parallelizable so that it can provide high throughput with low cost and low latency.

A. DAA

B. CCM

C. GCM

D. CTR

3. Insertion of messages into the network from a fraudulent source is a __________ attack.

A. content modification

B. masquerade

C. source repudiation

D. sequence modification

4. Confidentiality can be provided by performing message encryption __________ the MAC algorithm.

.

A. before

B. before or after

C. after

D. during

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. A __________ is an algorithm that requires the use of a secret key.

A. DAA

B. SHA

C. GCM

D. MAC

6. "Release of message contents to any person or process not possessing the appropriate cryptographic key" is a __________ attack.

A. content modification

B. source repudiation

C. disclosure

D. sequence modification

7. With _________ authentication an opponent would have difficulty generating ciphertext that when decrypted would have valid error control bits.

A. checksum

B. CMAC

C. cipher block chaining

D. internal error control

8. The MAC function is a __________ function.

A. one-to-many

B. many-to-one

C. one-to-one

D. one-to-two

9. The appeal of __________ is that its designers have been able to prove an exact relationship between the strength of the embedded hash function and the strength of this form of authentication.

A. MAC

B. HMAC

C. GMAC

D. CMAC

10. The _________ attack is when the attacker is looking for two messages M and M1 that produce the same hash: H(M) = H(M1)

.

A. birthday

B. chaining

C. MAC

D. hash

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. Two MACs that are based on the use of a block cipher mode of operation are Data Authentication Algorithm and __________ .

A. GMAC

B. DMAC

C. TMAC

D. CMAC

12. The key algorithmic ingredients of _________ are the AES encryption algorithm, the CTR mode of operation, and the CMAC authentication algorithm.

A. DAA

B. GCM

C. CCM

D. CMA

13. The GCM mode makes use of two functions: __________, which is a keyed hash function, and GCTR. A. CTR

B. HMAC

C. GHASH

D. CCM

14. The essential elements of any pseudorandom number generator are a __________ and a deterministic algorithm for generating a stream of pseudorandom bits.

A. secret key

B. session key

C. seed value

D. stream encryption function

15. The approach taken by the Transport Layer Security protocol and the Wireless Transport Layer Security Protocol involve invoking HMAC _________ for each block of output wi.

.

A. zero times

B. twice

C. three times

D. once

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. __________ assures that data received are exactly as sent and that the purposed identity of the sender is valid.

2. Discovery of the pattern of traffic between parties is a __________ attack.

3. A __________ takes a variable length message and a secret key as input and produces an authentication code.

4. One approach to constructing a MAC is to use a symmetric block cipher in such a way that it produces a __________ output for a variable length input.

5. Any modification to a sequence of messages between parties, including insertion, deletion, and reordering is a __________ attack.

6. The types of functions that may be used to produce an authenticator are grouped into three classes: hash function, message authentication code, and ___________ .

7. An alternative authentication technique involves the use of a secret key to generate a small fixed size block of data known as a __________ or MAC that is appended to the message.

8. When an entire message is encrypted for confidentiality using either symmetric or asymmetric encryption the security of the scheme generally depends on the __________ of the key.

9. Attacks on MACs can be grouped into two categories: brute-force attacks and __________ .

10. The __________ algorithm can be defined as using the cipher block chaining mode of operation of DES with an initialization vector of zero.

11. ___________ is a term used to describe encryption systems that simultaneously protect confidentiality and authenticity of communications.

12. The H→E approach is used in the __________ protocol to protect WiFi networks.

13. The __________ mode of operation was standardized by NIST specifically to support the security requirements of IEEE 802.1 WiFi wireless local area networks but can be used in any networking application requiring authenticated encryption.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

14. NIST SP 800-90, IEEE 802.11i, and TLS/WTLS are three ____________ based on HMAC. 15. HMAC is a widely used standardized _________ function and is implemented in many protocols and applications.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 13: DIGITAL SIGNATURES TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

F T F T F F T F T F T F T T T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

D D B A A D A A A D C A D A D

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

digital signature encoded message (EM) universal forgery be verifiable by third parties Digital Signature Algorithm (DSA) generic chosen message DSA direct digital signature ElGamal Schnorr 2n-bit integer RSA digital signature algorithm (DSA) elliptic curve timestamp

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 13: DIGITAL SIGNATURES TRUE OR FALSE T

F

1. A digital signature can guarantee the integrity but not the source of the message.

T

F

2. It must be computationally infeasible to forge a digital signature, either by constructing a new message for an existing digital signature or by constructing a fraudulent digital signature for a given message.

T

F

3. The global public key components for DSA are p, q, and h.

T

F

4. The most important development from the work on public-key cryptography is the digital signature.

T

F

5. The ElGamal signature scheme involves the use of the public key for encryption and the private key for decryption.

T

F

6. It is important in a direct digital signature to perform an outer confidentiality function first and then the signature function.

T

F

7. Message authentication protects two parties who exchange messages from any third party, however, it does not protect the two parties against each other.

T

F

8. The digital signature function does not include the authentication function.

T

F

9. The DSS approach makes use of a hash function.

T

F

10. It must be relatively difficult to recognize and verify the digital signature.

T

F

11. The Schnorr signature scheme is based on discrete logarithms.

T

F

12. The main work for signature generation depends on the message and is done during the idle time of the processor.

T

F

13. Unlike RSA, DSS cannot be used for encryption or key exchange.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. The global public key components of DSA are the same as for the Schnorr signature scheme.

T

F

15. The first part of the Schnorr digital signature scheme is the generation of a private/public key pair.

MULTIPLE CHOICE 1. The __________ is formed by taking the hash of the message and encrypting the message with the creator's private key.

A. timestamp

B. message digest

C. hash code

D. digital signature

2. __________ is where the attacker forges a signature for a particular message chosen by the attacker.

A. Total break

B. Universal forgery

C. Existential forgery

D. Selective forgery

3. The digital signature standard is a __________ standard that uses the secure hash algorithm.

A. IEEE

B. NIST

C. ISO

D. ITIL

4. With a __________ attack the attacker is given access to a set of messages and their signatures.

.

A. known message

B. key-only

C. directed chosen message

D. generic chosen message

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. Similar to the generic attack, except that the list of messages to be signed is chosen after the attacker knows the user's public key but before any signatures are seen, is the __________ attack.

A. directed chosen

B. key-only

C. adaptive chosen

D. known message

6. A __________ is where the attacker determines the user's private key.

A. universal forgery

B. selective forgery

C. existential forgery

D. total break

7. As with ElGamal encryption, the global elements of __________ are a prime number q and a, which is a primitive root of q.

A. ElGamal digital signature

B. digital signature standard

C. digital signature

D. direct digital signature

8. The _________________, which is the latest of the RSA schemes, is the one that RSA Laboratories recommends as the most secure of the RSA schemes.

A. RSA-PSS

B. ECDSA

C. DSA-SDS

D. EDSDS

9. The digital signature approach uses an algorithm that is designed to provide only the _________ function.

A. digital signature

B. ElGamal

C. DSA

D. timestamp

10. In the __________ approach only the sender knows the private key so only the sender could have produced a valid signature.

.

A. EDS

B. DSA

C. DSS

D. RSA

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. The ____________ components of DSA are the same as in the Schnorr signature scheme.

A. private key

B. EDS

C. global public key

D. message digest

12. To create a __________ a user calculates two quantities, r and s, that are functions of the public key components (p, q, g), the user's private key (x), the hash code of the message H(M), and an additional integer k that should be generated randomly or pseudorandomly and be unique for each signing.

A. signature

B. hash authentication

C. secret key

D. global key

13. The __________ scheme minimizes the message dependent amount of computation required to generate a signature.

A. Rabin

B. SHA-1

C. ElGamal

D. Schnorr

14. With a __________ attack the attacker is allowed to use the user as an "oracle".

This means that the user may request signatures of messages that depend on previously obtained message-signature pairs.

A. adaptive chosen message

B. generic chosen

C. directed chosen message

D. known message

15. In the digital signature algorithm the user's __________ is represented by x, which is a random or pseudorandom integer with 0 < x < q.

.

A. per message secret number

B. private key

C. global key

D. public key

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. A _________ is an authentication mechanism that enables the creator of a message to attach a code that acts as a signature.

2. The first stage in generating an RSA-PSS signature of a message M is to generate from M a fixed-length message digest, called an ______________.

3. The attacker finds an efficient signing algorithm that provides an equivalent way of constructing signatures on arbitrary messages is a ___________ .

4. A digital signature must have the following properties: it must verify the author and the date and time of the signature; it must authenticate the contents at the time of the signature; and it must ___________ to resolve disputes.

5. The DSS makes use of the Secure Hash Algorithm and presents a new digital signature technique known as the ______________ .

6. The __________ attack is where the attacker chooses a list of messages before attempting to break the user's signature scheme, independent of the user's public key. The attacker then obtains from the user valid signatures for the chosen messages.

7. _________ specifies that if the signature generation process results in a value of s = 0 a new value of k should be generated and the signature should be recalculated.

8. The term __________ refers to a digital signature scheme that involves only the communicating parties.

9. The __________ encryption scheme is designed to enable encryption by a user's public key with decryption by the user's private key.

10. The __________ scheme minimizes the message dependent amount of computation required to generate a signature.

11. The message dependent part of the Schnorr digital signature generation requires multiplying a __________ with an n-bit integer.

12. In addition to the NIST Digital Signature Algorithm and ECDSA, the 2009 version of FIPS 186 also includes several techniques based on _________ , all of which were developed by RSA Laboratories and are in wide use.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

13. The _________ is based on the difficulty of computing discrete logarithms and is based on schemes originally presented by ElGamal and Schnorr.

14. FIPS 186 -3 incorporates digital signature algorithms based on RSA and on __________ cryptography.

15. Administrative controls relating to the security of private keys can be employed by including a __________ (which includes date and time) and to require prompt reporting of compromised keys to a central authority.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 14: KEY MANAGEMENT AND DISTRIBUTION TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F T F T T F T F T F T T T F

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

B C D A B B A A C C B C C B C

© 2017 Pearson Education, Ltd. All rights reserved

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

Key distribution public-key infrastructure (PKI) X.509 public key application key distribution master nonce man-in-the-middle public-key authority certificate X.509 reverse certificates Registration repository

© 2017 Pearson Education, Ltd. All rights reserved

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 14: KEY MANAGEMENT AND DISTRIBUTION TRUE OR FALSE T

F

1. Some sort of mechanism or protocol is needed to provide for the secure distribution of keys.

T

F

2. A public-key certificate scheme alone does not provide the necessary security to authenticate the public key.

T

F

3. For symmetric encryption to work the two parties to an exchange must share the same key and that key must be protected from access by others.

T

F

4. X.509 defines the format for private-key certificates.

T

F

5. The topics of cryptographic key management and cryptographic key distribution are complex, involving cryptographic, protocol, and management considerations.

T

F

6. Frequent key changes are usually desirable to limit the amount of data compromised if an attacker learns the key.

T

F

7. For link encryption manual delivery is awkward.

T

F

8. Each user must share a unique key with the key distribution center for purposes of key distribution.

T

F

9. Typically the session key is used for the duration of a logical connection, such as a frame relay connection or transport connection, and then it is permanently stored.

T

F

10. Master keys can be distributed in some noncryptographic way such as physical delivery.

T

F

11. A random number would not be a good choice for a nonce.

T

F

12. The distribution of session keys delays the start of any exchange and places a burden on network capacity.

T

F

13. Although public announcement of public keys is convenient, anyone can forge a public announcement.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. X.509 is an important standard because the certificate structure and authentication protocols defined in X.509 are used in a variety of contexts.

T

F

15. Because certificates are forgeable they cannot be placed in a directory without the need for the directory to make special efforts to protect them.

MULTIPLE CHOICE 1. Key distribution often involves the use of __________ which are infrequently used and are long lasting.

A. private key certificates

B. master keys

C. session keys

D. public key certificates

2. __________ key encryption schemes are secure if the public key is authenticated.

A. Message

B. Management

C. Public

D. Private

3. A __________ defines the procedures needed to revoke digital certificates.

A. KDC

B. digital key

C. cryptographic key encryption

D. public key infrastructure

4. _________ implementations make use of X.509 certificates.

.

A. PKI

B. CDC

C. HMAC

D. KDC

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. Key distribution often involves the use of _________ which are generated and distributed for temporary use between two parties.

A. public key certificates

B. session keys

C. master keys

D. private key certificates

6. The strength of any cryptographic system rests with the ___________ .

A. end encryption

B. key distribution technique

C. nonce

D. X.509 certificate

7. If __________ is done at a network or IP level a key is needed for each pair of hosts on the network that wish to communicate.

A. end-to-end encryption

B. key management

C. key distribution

D. link encryption

8. Communication between end systems is encrypted using a _________ key.

A. session

B. master

C. permanent

D. message

9. The more frequently session keys are exchanged the more __________ they are because the opponent has less ciphertext to work with for any given session key.

A. insecure

B. streamlined

C. secure

D. obsolete

10. One of the most important uses of a __________ cryptosystem is to encrypt secret keys for distribution.

.

A. master key

B. KDC

C. public key

D. end-to-end

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. With the __________ scheme, if an adversary succeeds in obtaining or computing the private key of the directory authority, the adversary could authoritatively pass out counterfeit public keys and subsequently impersonate any participant and eavesdrop on messages sent to any participant.

A. public key authority

B. publicly available directory

C. public key certificates

D. public announcement

12. The principal objective for developing a _________ is to enable secure, convenient and efficient acquisition of public keys.

A. KDC

B. IETF

C. PKI

D. CRL

13. __________ is an integer value unique within the issuing CA that is unambiguously associated with this certificate.

A. Signature identifier

B. Version

C. Serial number

D. Issuer unique identifier

14. __________ indicates a restriction imposed as to the purposes for which, and the policies under which, the certified public key may be used.

A. Authority key identifier

B. Key usage

C. Subject key identifier

D. Certificate policies

15. The __________ is the issuer of certificates and certificate revocation lists and may also support a variety of administrative functions.

.

A. CRL issuer

B. certified user

C. certification authority

D. registration authority

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1. __________ is the function that delivers a key to two parties who wish to exchange secure encrypted data.

2. A _________ is defined as the set of hardware, software, people, policies, and procedures needed to create, manage, store, distribute, and revoke digital certificates based on asymmetric cryptography.

3. Used in a variety of applications, __________ defines the format for public-key certificates.

4. Public-key encryption schemes are secure only if the authenticity of the ___________ is assured.

5. If encryption is done at the __________ level a key is needed for every pair of users or processes that require communication.

6. If A and B each has an encrypted connection to a third party C, C can deliver a key on the encrypted links to A and B. A _________ center is responsible for distributing keys to pairs of users as needed.

7. Session keys are transmitted in encrypted form using a __________ key that is shared by the key distribution center and an end system or user.

8. A unique identifier for a transaction is a __________ and this identifier may be a timestamp, a counter or a random number, with the minimum requirement being that it differs with each request.

9. A __________ attack is when a protocol is insecure against an adversary who can intercept messages and can either relay the intercepted message or substitute another message.

10. Several techniques have been proposed for the distribution of public keys.

The proposals can be grouped into the following four general schemes: public announcement, publicly available directory, public-key certificates, and ____________.

11. A __________ consists of a public key, an identifier of the key owner, and the whole block signed by a trusted third party and can be used by participants to exchange keys without contacting a public key authority in a way that is as reliable as if the keys were obtained directly from a public key authority.

12. __________ certificates are used in most network security applications including IP security, transport layer security and S/MIME. .

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

13. The directory entry for each certification authority includes two types of certificates: forward certificates and ___________ .

14. __________ is the process whereby a user first makes itself known to a certification authority prior to that certification authority issuing a certificate for that user.

15. A _________ is a generic term used to denote any method for storing certificates and CRLs so that they can be retrieved by end entities.

.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 15: USER AUTHENTICATION PROTOCOLS TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F F T T F T T T F F T T F F

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

A C D A B C B B A A C B B A B

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

.

Mutual authentication Kerberos does ticket verification Identity management transparent token key distribution center (KDC) suppress-replay Kerberos authentication server (AS) ticket-granting server (TGS) propagating cipher block chaining (PCBC) federated identity management

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 15: USER AUTHENTICATION PROTOCOLS TRUE OR FALSE T

F

1. Kerberos provides a trusted third party authentication service that enables clients and servers to establish authenticated communication.

T

F

2. Examples of dynamic biometrics include recognition by fingerprint, retina, and face.

T

F

3. User authentication is the means by which a user provides a claimed identity to the system.

T

F

4. Identity federation is in essence an extension of identity management to multiple security domains.

T

F

5. User authentication is the basis for most types of access control and for user accountability.

T

F

6. For network based user authentication the most important methods involve cryptographic keys and something the individual possesses, such as a smart card.

T

F

7. There are a variety of problems including dealing with false positives and false negatives, user acceptance, cost, and convenience with respect to biometric authenticators.

T

F

8. Any timestamp based procedure must allow for a window of time sufficiently large enough to accommodate network delays yet sufficiently small to minimize the opportunity for attack.

T

F

9. An e-mail message should be encrypted such that the mail handling system is not in possession of the decryption key.

T

F

10. Because there are no potential delays in the e-mail process, timestamps are extremely useful.

T

F

11. The operating system cannot enforce access-control policies based on user identity.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

12. The security of the Kerberos server should not automatically be assumed, but must be guarded carefully by taking precautions such as placing the server in a locked room.

T

F

13. Once the server verifies that the user ID in the ticket is the same as the unecrypted user ID in the message it considers the user authenticated and grants the requested service.

T

F

14. It is the ticket that proves the client's identity.

T

F

15. Identity providers may also assign attributes to users, such as roles, access permissions, and employee information.

MULTIPLE CHOICE 1. __________ is an authentication service designed for use in a distributed environment.

A. Kerberos

B. PCBC

C. Toklas

D. X.509

2. The __________ approach is unsuitable for a connectionless type of application because it requires the overhead of a handshake before any connectionless transmission, effectively negating the chief characteristic of a connectionless transaction.

A. timestamp

B. backward reply

C. challenge-response

D. replay

3. A common item of authentication information associated with a user is a ___________ .

A. nonce

B. timestamp

C. ticket

D. password

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

4. The overall scheme of Kerberos is that of a trusted third party authentication service that uses a protocol based on a proposal by __________ .

A. Needham and Schroeder

B. Kehn

C. Denning

D. Gong

5. ________ is a procedure that allows communicating parties to verify that the contents of a received message have not been altered and that the source is authentic.

A. Identification

B. Message authentication

C. Verification

D. User authentication

6. Presenting an identifier to the security system is the __________ step.

A. authentication

B. verification

C. identification

D. clarification

7. Presenting or generating authentication information that corroborates the binding between the entity and the identifier is the ___________ step.

A. identification

B. verification

C. clarification

D. authentication

8. The __________ is unsuitable for a connectionless type of application because it requires the overhead of a handshake before any connectionless transmission, effectively negating the chief characteristic of a connectionless transaction.

A. timestamp approach

B. challenge-response approach

C. simple replay approach

D. one-way authentication approach

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

9. Kerberos relies exclusively on __________ .

A. symmetric encryption

B. asymmetric encryption

C. private key encryption

D. public key encryption

10. A Kerberos __________ is a set of managed nodes that share the same Kerberos database.

A. realm

B. TGS

C. network

D. principal

11. In an unprotected network environment any client can apply to any server for service. The obvious security risk of this is __________ .

A. certification

B. authentication

C. impersonation

D. authorization

12. A service to solve the problem of minimizing the number of times that a user has to enter a password and the risk of an eavesdropper capturing the password and using it is known as the __________ .

A. authentication server

B. ticket granting server

C. Kerberos mutual authentication

D. PCBC mode

13. A centralized, automated approach to provide enterprise-wide access to resources by employees and other authorized individuals with a focus of defining an identity for each user, associating attributes with the identity, and enforcing a means by which a user can verify identity is __________ .

A. enterprise management

B. identity management

C. federated identity management

D. realm management

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

14. __________ is an extension of identity management to multiple security domains such as autonomous internal business units, external business partners and other third party applications and services with the goal of sharing digital identities so that a user can be authenticated a single time and then access applications and resources across multiple domains.

A. Identity federation

B. Kerberos

C. Attribute service

D. Data security management

15. The principal underlying standard for federated identity is the __________ which defines the exchange of security information between online business partners.

A. OSAIS

B. SAML

C. RBAC

D. SFIL

SHORT ANSWER 1. _________ protocols enable communicating parties to satisfy themselves mutually about each other's identity and to exchange session keys.

2. __________ in Greek mythology is a three headed dog with a serpent's tail that guards the entrance of Hades.

3. There are four general means of authenticating a user's identity. They are: something the individual knows, something the individual possesses, something the individual is, and something the individual __________ .

4. To convince the server that a user is authentic, the authentication server creates a _________ that contains the user's ID and network address and the server's ID and sends it back to the client so they can continue the request for service.

5. An authentication process consists of two steps: identification step and __________ step.

6. ____________ is a centralized, automated approach to provide enterprise wide access to resources by employees and other authorized individuals.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

7. The first published report on Kerberos listed the following requirements: secure, reliable, scalable and __________ .

8. Examples of something the individual possesses would include cryptographic keys, electronic keycards, smart cards, and physical keys. This type of authenticator is referred to as a __________ .

9. The _________ is responsible for generating keys to be used for a short time over a connection between two parties and for distributing those keys using the master keys to protect the distribution.

10. A __________ attack is where an opponent intercepts a message from the sender and replays it later when the timestamp in the message becomes current at the recipient's site.

11. __________ is an authentication service developed as part of Project Athena at MIT. 12. A solution, which eliminates the burden of each server having to confirm the identities of clients who request service, is to use an __________ that knows the passwords of all users and stores these in a centralized database and shares a unique secret key with each server.

13. The ticket granting ticket is encrypted with a secret key known only to the AS and the __________ .

14. Intended to provide an integrity check as part of the encryption operation, encryption in Kerberos Version 4 makes use of a nonstandard mode of DES known as ____________. It has been demonstrated that this mode is vulnerable to an attack involving the interchange of ciphertext blocks.

15. A concept dealing with the use of a common identity management scheme across multiple enterprises and numerous applications and refers to the agreements, standards, and technologies that enable the portability of identities, identity attributes, and entitlements across multiple enterprises and numerous applications and supporting many thousands, even millions, of users is _________ .

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 16: NETWORK ACCESS CONTROL AND CLOUD SECURITY TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T T F T T T F T F T T T T F T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

C A B D A C B B A C A D C A D

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

Network access server (NAS) Enforcement firewall authentication server supplicant Cloud computing infrastructure hybrid cloud cloud carrier Identity and access management (IAM) Security assessments EAP-TLS EAP-GPSK EAP authenticator Security as a service (SecaaS)

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 16: NETWORK ACCESS CONTROL AND CLOUD SECURITY TRUE OR FALSE T

F

1. Network access control authenticates users logging into the network and determines what data they can access and actions they can perform.

T

F

2. Access requestors are also referred to as clients.

T

F

3. A network access server does not include its own authentication services.

T

F

4. VLANs are common NAC enforcement methods.

T

F

5. The Extensible Authentication Protocol supports multiple authentication methods.

T

F

6. EAPOL operates at the network layers and makes use of an IEEE 802 LAN, such as Ethernet or Wi-Fi, at the link level.

T

F

7. There is a decreasing trend in organizations to move information technology operations to a cloud computing infrastructure.

T

F

8. Cloud computing gives you the ability to expand and reduce resources according to your specific service requirement.

T

F

9. The cloud provider in a private cloud infrastructure is responsible for both the infrastructure and the control.

T

F

10. The NIST cloud computing reference architecture focuses on the requirements of “what” cloud services provide, not a “how to” design solution and implementation.

T

F

11. A cloud broker is useful when cloud services are too complex for a cloud consumer to easily manage.

T

F

12. For many clients, the most devastating impact from a security breach is the loss or leakage of data.

T

F

13. In using cloud infrastructures, the client necessarily cedes control to the CP on a number of issues that may affect security.

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. The threat of data compromise decreases in the cloud.

T

F

15. Data must be secured while at rest, in transit, and in use, and access to the data must be controlled.

MULTIPLE CHOICE 1. ___________ is an umbrella term for managing access to a network.

A. NAS

B. ARC

C. NAC

D. RAS

2. The _________ is the node that is attempting to access the network and may be any device that is managed by the network access control system.

A. AR

B. RAS

C. IP

D. PS

3. The __________ determines what access should be granted.

A. authentication server

B. policy server

C. supplicant

D. access requestor

4. The __________ is an Internet protocol that enables dynamic allocation of IP addresses to hosts.

A. VLAN

B. IEEE 802.1X

C. EAPS

D. DHCP

5. _________ is a client computer that is attempting to access a network.

A. EAP peer

B. PSK

C. NAC

D. RAS

6. Broad network access, measured service, resource pooling, and rapid elasticity are essential characteristics of ___________.

A. PaaS

B. network access control

C. cloud computing

D. EAP-TLS

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

7. _________ saves the complexity of software installation, maintenance, upgrades, and patches.

A. IaaS

B. SaaS

C. EAP

D. DHCP

8. In effect, ________ is an operating system in the cloud.

A. IEEE 802.1X

B. PaaS

C. IaaS

D. DHCP

9. _________ enables customers to combine basic computing services, such as number crunching and data storage, to build highly adaptable computer systems.

A. IaaS

B. EAP peer

C. CP

D. SaaS

10. With a _________ infrastructure, the cloud infrastructure is made available to the general public or a large industry group and is owned by an organization selling cloud services.

A. hybrid cloud

B. private cloud

C public cloud

D. community cloud

11. With a _________ infrastructure, the cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns.

A. community cloud

B. public cloud

C. private cloud

D. hybrid cloud

12. A _________ is a person or organization that maintains a business relationship with, and uses service from, cloud providers.

A. cloud auditor

B. cloud broker

C. cloud carrier

D. cloud consumer

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

13. A ________ is a person, organization, or entity responsible for making a service available to interested parties.

A. cloud broker

B. cloud auditor

C. cloud provider

D. cloud carrier

14. A ________ is a party that can conduct independent assessment of cloud service, information sytem operations, performance, and security of the cloud implementation.

A. cloud auditor

B. cloud carrier

C. cloud broker

D. all of the above

15. _________ is the provision of security applications and services via the cloud either to cloud-based infrastructure and software or from the cloud to the customers’ on-premise systems.

A. IaaS

B. PaaS

C. SaaS

D. SecaaS

SHORT ANSWER 1. The ___________ functions as an access control point for users in remote locations connecting to an enterprise’s internal network.

2. __________ methods are the actions that are applied to ARs to regulate access to the enterprise network.

3. A __________ provides a form of NAC by allowing or denying network traffic between an enterprise host and an external user.

4. An __________ is a server computer that negotiates the use of a specific EAP method with an EAP peer, validates the EAP peer’s credentials, and authorizes access to the network.

5. A _________ is an entity at one end of a point-to-point LAN segment that seeks to be authenticated by an autheticator attached to the other end of that link.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. _________ is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction.

7. NIST defines three service models, which can be viewed as nested service alternatives: software as a service, platform as a service, and _________ as a service.

8. With a ________ infrastructure, the cloud infrastructure is a composition of two or more clouds that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability.

9. A _________ in an intermediary that provides connectivity and transport of cloud services from CP’s to cloud consumers.

10. ___________ includes people, processes, and systems that are used to manage access to enterprise resources by assuring that the identity of an entity is verified, and then granting the correct level of access based on this assured identity.

11. __________ are third party audits of cloud services.

12. _________ defines how the TLS protocol can be encapsulated in EAP messages.

13. ____________ is an EAP method for mutual authentication and session key derivation using a Pre-Shared Key. 14. An _________ is an access point or NAS that requires EAP authentication prior to granting access to a network.

15. The Cloud Security Alliance defines _______ as the provision of security applications and services via the cloud either to cloud-based infrastructure and software or from the cloud to the customers’ on-premise systems.

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 17: TRANSPORT-LEVEL SECURITY TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F T F T T F T F T F F T T T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

D B A B D A B B A B A A C D B

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

TLSv1.3 Handshake Passive message integrity Record Protocol HTTPS connection SSH Alert Protocol Ephemeral Diffie-Hellman private key remote forwarding CipherSpecs Pseudorandom Function (PRF) Local forwarding

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 17: TRANSPORT-LEVEL SECURITY TRUE OR FALSE T

F

1. A TLS session is an association between a client and a server.

T

F

2. Secure Sockets Layer (SSL) is an Internet standard that evolved from a commercial protocol known as Transport Layer Security (TLS).

T

F

3. Sessions are used to avoid the expensive negotiation of new security parameters for each connection that shares security parameters.

T

F

4. The Handshake Protocol is the simplest of the four TLS-specific protocols that use the TLS Record Protocol.

T

F

5. The World Wide Web is fundamentally a client/server application running over the Internet and TCP/IP intranets.

T

F

6. One way to classify Web security threats is in terms of the location of the threat: Web server, Web browser, and network traffic between browser and server.

T

F

7. The encryption of the compressed message plus the MAC must increase the content length by more than 1024 bytes.

T

F

8. The Change Cipher Spec Protocol is one of the four TLS-specific protocols that use the SSL Record Protocol.

T

F

9. The SSL Record Protocol is used before any application data is transmitted.

T

F

10. The first element of the CipherSuite parameter is the key exchange method.

T

F

11. The certificate message is required for any agreed on key exchange method except fixed Diffie-Hellman.

T

F

12. Phase 3 completes the setting up of a secure connection of the Handshake Protocol.

T

F

13. The shared master secret is a one-time 48-byte value generated for a session by means of secure key exchange.

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. SSL/TLS attacks can be grouped into four general categories: attacks on the handshake protocol, attacks on the record and application data protocols, attacks on the PKI, and other attacks.

T

F

15. Server authentication occurs at the transport layer, based on the server possessing a public/private key pair.

MULTIPLE CHOICE 1. The SSL Internet standard version is called _________ .

A) SSH

B) HTTP

C) SLP

D) TLS

2. The most complex part of TLS is the __________ .

A) SSL Record Protocol

B) Handshake Protocol

C) Change Cipher Spec Protocol

D) Alert Protocol

3. _________ attacks include impersonating another user, altering messages in transit between client and server and altering information on a Web site.

A) Active

B) Passive

C) Shell

D) Psuedo

4. The symmetric encryption key for data encrypted by the client and decrypted by the server is a _________ .

A) server write key C) sequence key

B) client write key D) master key

5. _________ provides secure, remote logon and other secure client/server facilities.

A) SLP

B) HTTPS

C) TLS

D) SSH

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. An TSL session is an association between a client and a server and is created by the ___________ .

A) Handshake Protocol

B) user

C) Spec Protocol

D) administrator

7. An arbitrary byte sequence chosen by the server to identify an active or resumable session state is a _________ .

A) peer certificate

B) session identifier

C) compression

D) cipher spec

8. The _________ is used to convey TLS-related alerts to the peer entity.

A) Change Cipher Spec Protocol C) SSL Record Protocol

B) Alert Protocol D) Handshake Protocol

9. With each element of the list defining both a key exchange algorithm and a CipherSpec, the list that contains the combination of cryptographic algorithms supported by the client in decreasing order of preference is the __________ .

A) CipherSuite

B) Random

C) Session ID

D) Version

10. Phase _________ of the Handshake Protocol establishes security capabilities.

A) 4

B) 1

C) 2

D) 3

11. The __________ approach is vulnerable to man-in-the-middle attacks.

A) Anonymous Diffie-Hellman

B) Fixed Diffie-Hellman

C) Remote Diffie-Hellman Hellman © 2017 Pearson Education, Ltd. All rights reserved.

D) Synchronous Diffie-

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

12. The final message in phase 2, and one that is always required, is the ___________ message, which is sent by the server to indicate the end of the server hello and associated messages.

A) server_done

B) no_certificate

C) goodbye

D) finished

13. A ______ is an identifier of a user of TCP. A)

protocol

C) seed

B) port D) shell

14. A PseudoRandom Function takes as input: A) a secret value

B) an identifying label

C) a seed value

D) all of the above

15. _________ is organized as three protocols that typically run on top of TCP for secure network communications and are designed to be relatively simple and inexpensive to implement.

A) SSL

B) SSH

C) TLS

D) SSI

SHORT ANSWER 1. __________ uses Diffie-Hellman or Elliptic Curve Diffie-Hellman for key exchange and does not permit RSA. 2. The _________ Protocol allows the server and client to authenticate each other and to negotiate an encryption and MAC algorithm along with cryptographic keys to be used to protect data sent in a TLS Record.

3. _________ attacks include eavesdropping on network traffic between browser and server and gaining access to information on a Web site that is supposed © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

to be restricted.

4. The TLS Record Protocol provides two services for TLS connections: confidentiality and ___________ .

5. The _________ takes an application message to be transmitted, fragments the data into manageable blocks, optionally compresses the data, applies a MAC, encrypts, adds a header, and transmits the resulting unit in a TCP segment.

6. __________ refers to the combination of HTTP and SSL to implement secure communication between a Web browser and a Web server.

7. Two important TLS concepts are the TLS session and the TLS _________ .

8. Three standardized schemes that are becoming increasingly important as part of Web commerce and that focus on security at the transport layer are: SSL/TLS, HTTPS, and _________.

9. Three higher-layer protocols defined as part of TLS are: The Handshake Protocol, The Change Cipher Spec Protocol, and the __________ .

10. _________ would appear to be the most secure of the three Diffie-Hellman options because it results in a temporary, authenticated key.

11. A signature is created by taking the hash of a message and encrypting it with the sender's _________ .

12. With __________ , the user’s SSH client receives traffic with a given destination port number, places the traffic on the correct port and sends it to the destination the user chooses.

13. _________ require a client write MAC secret, a server write MAC secret, a client write key, a server write key, a client write IV, and a server write IV, which are generated from the master secret in that order.

14. TLS makes use of a pseudorandom function referred to as __________ to expand secrets into blocks of data for purposes of key generation or validation.

15. __________ allows the client to set up a "hijacker" process that will intercept selected application-level traffic and redirect it from an unsecured TCP connection to a secure SSH tunnel.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 18: WIRELESS NETWORK SECURITY TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T T F T T T F F T T F T T T F

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

B A A C C A A C B C B C A D D

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

wireless medium denial of service (DoS) Distribution Wireless Ethernet Compatibility Alliance (WECA) coordination Group Temporal Key (GTK) extended service set (ESS) media access control (MAC) basic service set (BSS) Wi-Fi Protected Access (WPA) secure key delivery pairwise keys 4-way handshake IEEE 802.1X physical

© 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 18: WIRELESS NETWORK SECURITY TRUE OR FALSE T

F

1. IEEE 802.11 is a standard for wireless LANs.

T

F

2. Wireless networks, and the wireless devices that use them, introduce a host of security problems over and above those found in wired networks.

T

F

3. Sensors and robots, are not vulnerable to physical attacks.

T

F

4. The integration service enables transfer of data between a station on an IEEE 802.11 LAN and a station on an integrated IEEE 802.x LAN.

T

F

5. MAC spoofing occurs when an attacker is able to eavesdrop on network traffic and identify the MAC address of a computer with network privileges.

T

F

6. The DS can be a switch, a wired network, or a wireless network.

T

F

7. The pairwise master key is derived from the group key.

T

F

8. IEEE 802.11 defines seven services that need to be provided by the wireless LAN to achieve functionality equivalent to that which is inherent to wired LANs.

T

F

9. Handheld PDAs pose a security risk in terms of both eavesdropping and spoofing.

T

F

10. The actual method of key generation depends on the details of the authentication protocol used.

T

F

11. The use of 802.1X cannot prevent rogue access points and other unauthorized devices from becoming insecure backdoors.

T

F

12. The principal threats to wireless transmission are eavesdropping, altering or inserting messages, and disruption.

T

F

13. The use of encryption and authentication protocols is the standard method of countering attempts to alter or insert transmissions.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. You should allow only specific computers to access your wireless network.

T

F

15. Security policies for mobile devices should assume that any mobile device will not be stolen or accessed by a malicious party.

MULTIPLE CHOICE 1. The term used for certified 802.11b products is ___________ .

A. WAP

B. Wi-Fi

C. WEP

D. WPA

2. The layer of the IEEE 802 reference model that includes such functions as encoding/decoding of signals and bit transmission/reception is the _________ .

A. physical layer

B. control layer

C. logical link layer

D. media access layer

3. In a(n) __________ situation, a wireless device is configured to appear to be a legitimate access point, enabling the operator to steal passwords from legitimate users and then penetrate a wired network through a legitimate wireless access point.

A. malicious association

B. identiy theft

C. network injection

D. ad hoc network

4. ___________ and links, such as personal network Bluetooth devices, barcode readers, and handheld PDAs, pose a security risk in terms of both eavesdropping and spoofing.

A. DoS

B. Accidental association

C. Nontraditional networks

D. Ad hoc networks

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. The function of the __________ is to on transmission assemble data into a frame, on reception disassemble frame and perform address recognition and error detection, and govern access to the LAN transmission medium.

A. transmission layer

B. logical layer

C. media access control layer

D. physical layer

6. The master session key is also known as the __________ key.

A. AAA

B. GTK

C. MIC

D. STA

7. The __________ is the information that is delivered as a unit between MAC users.

A. MSDU

B. DS

C. MPDU

D. BSS

8. The __________ layer keeps track of which frames have been successfully received and retransmits unsuccessful frames.

A. transmission

B. media access control

C. logical link control

D. physical layer

9. The purpose of the discovery phase in the ___________ is for a STA and an AP to recognize each other, agree on a set of security capabilities, and establish an association for future communication using those security capabilities.

A. WPA

B. RSN

C. TKIP

D. WAE

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

10. The specification of a protocol along with the chosen key length is known as a __________ .

A. extended service

B. distribution system

C. cipher suite

D. RSN

11. The _________ is used to ensure the confidentiality of the GTK and other key material in the 4-Way Handshake.

A. MIC key

B. EAPOL-KEK

C. EAPOL-KCK

D. TK

12. The PMK is used to generate the _________ which consists of three keys to be used for communication between a STA and AP after they have been mutually authenticated.

A. AAA Key

B. GTK

C. PTK

D. PSK

13. A __________ is any device that contains an IEEE 802.11 conformant MAC and physical layer.

A. station

B. MPU

C. service data unit

D. MSDU

14. The first 802.11 standard to gain broad industry acceptance was _________.

A. 802.11i

B. 802.11a

C. 802.11g

D. 802.11b

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

15. ____________ can occur when a company’s wireless LAN or wireless access points to wired LANs in close proximity and may create overlapping transmission ranges. A user intending to connect to one LAN may unintentionally lock on to a wireless access point from a neighboring network.

A. Network injection

B. Denial of service attacks

C. Man-in-the-middle attacks

D. Accidental association

SHORT ANSWER 1. In simple terms, the wireless environment consists of three components that provide point of attack: the endpoint, the ______________, and the access point.

2. A __________ attack occurs when an attacker continually bombards a wireless access point or some other accessible wireless port with various protocol messages designed to consume system resources.

3. __________ is the primary service used by stations to exchange MPDUs when the MPDUs must traverse the DS to get from a station in one BSS to a station in another BSS. 4. To certify interoperability for 802.11b products an industry consortium named the __________ was formed.

5. The __________ function is the logical function that determines when a station operating within a BSS is permitted to transmit and may be able to receive PDUs. 6. Derived from the GMK, the _________ is used to provide confidentiality and integrity protection for multicast/broadcast user traffic.

7. An __________ is a set of one or more interconnected BSSs and integrated LANs that appear as a single BSS to the LLC layer at any station associated with one of these BSSs. 8. The __________ layer is responsible for detecting errors and discarding any frames that contain errors.

9. The smallest building block of a wireless LAN is a __________ which consists of wireless stations executing the same MAC protocol and competing for access to the same shared wireless medium. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

10. In order to accelerate the introduction of strong security into WLANs, the Wi-Fi Alliance promulgated __________ as a set of security mechanisms for the Wi-Fi standard.

11. The MPDU authentication phase consists of three phases. They are: connect to AS, EAP exchange and _________ .

12. Forming a hierarchy beginning with a master key from which other keys are derived dynamically and used for a limited period of time, __________ are used for communication between a pair of devices typically between a STA and an AP. 13. The MPDU exchange for distributing pairwise keys is known as the _________ which the STA and SP use to confirm the existence of the PMK, to verify the selection of the cipher suite, and to derive a fresh PTK for data sessions.

14. The main threat involving wireless access points is unauthorized access to the network. The principal approach for preventing success is the __________ standard for port-based network access control.

15. The IEEE 802.11 protocol stack consists of the logical link control layer, the medium access control layer, and the _________ layer.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 19: ELECTRONIC MAIL SECURITY TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F T T F T F T F T F T T T F

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

A D A D A B B B B C D D B B D

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

Pretty Good Privacy (PGP) Key Distribution confidentiality radix-64 Sender Policy Framework (SPF) forensics Secure/Multipurpose Internet Mail Extension (S/MIME) Content-Type application quoted-printable base64 DNS-Based Authentication of Named Entities (DANE) Domain Name System (DNS) DomainKeys Identified Mail (DKIM) CompressedData

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 19: ELECTRONIC MAIL SECURITY TRUE OR FALSE T

F

1. “Pretty Good Privacy” is an alternative email security protocol.

T

F

2. An Administrative Management Domain is a directory lookup service that provides a mapping between the name of a host on the Internet and its numerical address.

T

F

3. E-mail is the most common distributed application that is widely used across all architectures and vendor platforms.

T

F

4. A Message Transfer Agent is like a packet switch or IP router in that its job is to make routing assessments and to move the message closer to recipients.

T

F

5. A Message Store cannot be located on the same machine as a MUA.

T

F

6. RFC 5322 defines a format for text messages that are sent using electronic mail.

T

F

7. SMTP can transmit executable files and other binary objects.

T

F

8. The bulk of the MIME specification is concerned with the definition of a variety of content types.

T

F

9. Native form is a format, appropriate to the content type, that is standardized for use between systems.

T

F

10. Base64 transfer encoding is also known as radix-64.

T

F

11. Integrity-related email security threats could result in unauthorized disclosure of sensitive information.

T

F

12. The MIME-Version field must have the parameter value 1.0 in order for the message to conform to RFCs 2045 and 2046.

T

F

13. For the text type of body no special software is required to get the full meaning of the text aside from support of the indicated character set.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. The objective of MIME Transfer Encodings is to provide reliable delivery across the largest range of environments.

T

F

15. DKIM is designed to provide an email authentication technique that is not transparent to the end user.

MULTIPLE CHOICE 1. __________ is a security enhancement to the MIME Internet email format standard based on technology from RSA Data Security.

A. S/MIME

B. SPF

C. DKIM

D. HTTPS

2. S/MIME provides authentication through the use of _________ .

A. asymmetric block encryption

B. symmetric block encryption

C. radix-64

D. digital signatures

3. S/MIME provides e-mail compatibility using the __________ encoding scheme.

A. radix-64

B. MIME

C. digital signature

D. symmetric block

4. __________ email security threats could prevent end users from being able to send or receive email.

A. Authenticity-related

B. Integrity-related

C. Confidentiality-related

D. Availability-related

5. There are ______ types of protocols used for transferring email.

A. two

B. four

C. six

D. three

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. MIME is an extension to the ________ framework that is intended to address some of the problems and limitations of the use of SMTP. A. RFC 821

B. RFC 5322

C. RFC 3852

D. RFC 4871

7. The ________ MIME field is a text description of the object with the body; this is useful when the object is not readable (e.g. audio data).

A. Content-Type

B. Content-Description

C. Content-ID

D. Content-Transfer-Encoding

8. The __________ field is used to identify MIME entities uniquely in multiple contexts.

A. Content-Transfer- Encoding

B. Content-ID

C. Content-Description

D. Content-Type

9. Video content will be identified as _________ format.

A. GIF

B. MPEG

C. BMP

D. JPEG

10. The __________ subtype is used when there are multiple independent body parts that need to be bundled in a particular order.

A. multipart/digest

B. multipart/parallel

C. multipart/mixed

D. multipart/alternative

11. For the __________ subtype the order of the parts is not significant.

A. multipart/mixed

B. multipart/digest

C. multipart/alternative

D. multipart/parallel

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

12. S/MIME cryptographic algorithms use __________ to specify requirement level.

A. CAN and MUST

B. SHOULD and CAN

C. SHOULD and MIGHT

D. SHOULD and MUST

13. ___________ allows email senders to specify policy on how their mail should be handled, the types of reports that receivers can send back, and the frequency those reports should be sent.

A. MUA

B. DMARC

C. DKIM

D. MTA

14. The _________ accepts the message submitted by a Message User Agent and enforces the policies of the hosting domain and the requirements of Internet standards.

A. Message Store

B. Mail Submission Agent

C. Message Transfer Agent

D. Mail Delivery Agent

15. Typically housed in the user's computer, a _________ is referred to as a client e-mail program or a local network e-mail server.

A. Mail Submission Agent

B. Message Transfer Agent

C. Message Store

D. Message User Agent

SHORT ANSWER 1. ___________ is an open-source, freely available software package for e-mail security which has essentially the same functionality as S/MIME. 2. There are two significant differences between S/MIME and OpenPGP: key certification and _____________.

3. S/MIME provides for four message-related services: authentication, _________ , compression, and email compatibility. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

4. To provide transparency for e-mail applications, an encrypted message may be converted to an ASCII string using _________ conversion.

5. ________ is the standardized way for a sending domain to identify and assert the mail senders for a given domain.

6. The two types of reports that DMARC reporting provides are aggregate reports and _________ reports.

7. __________ is a security enhancement to the MIME Internet e-mail format standard based on technology from RSA Data Security.

8. The __________ MIME field describes the data contained in the body with sufficient detail that the receiving user agent can pick an appropriate agent or mechanism to represent the data to the user or otherwise deal with the data in an appropriate manner.

9. The _________ type refers to other kinds of data, typically either uninterpreted binary data or information to be processed by a mail-based application.

10. The _________ transfer encoding is useful when the data consists largely of octets that correspond to printable ASCII characters.

11. The _________ transfer encoding, also known as radix-64 encoding, is a common one for encoding arbitrary binary data in such a way as to be invulnerable to the processing by mail-transport programs.

12. _________ is a protocol to allow X.509 certificates, commonly used for Transport Layer Security (TLS), to be bound to DNS names using DNSSEC. 13. ___________ is a directory lookup service that provides a mapping between the name of a host on the Internet and its numeric IP address.

14. __________ is a specification for cryptographically signing e-mail messages, permitting a signing domain to claim responsibility for a message in the mail stream; message recipients can verify the signature by querying the signer's domain directly to retrieve the appropriate public key and thereby confirming that the message was attested to by a party in possession of the private key for the signing domain.

15. S/MIME uses the following message content types: Data, SignedData, EnvelopedData, and ___________ .

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 20: IP SECURITY

TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T T F T F T T F T F T T F T T

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

B C A D C A D C B D C B C B D

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

confidentiality Tunnel security association database (SAD) encapsulating security payload replay HMAC Security Parameters Index (SPI) key management Encapsulating Security Payload IP Local IP Address security association bundle Oakley Key Determination Protocol digital signatures Certificate Request

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 20: IP SECURITY TRUE OR FALSE T

F

1. IP security is a capability that can be added to either current version of the Internet Protocol by means of additional headers.

T

F

2. The principal feature of IPsec is that it can encrypt and/or authenticate all traffic at the IP level.

T

F

3. Transport mode provides protection to the entire IP packet.

T

F

4. Additional padding may be added to provide partial traffic flow confidentiality by concealing the actual length of the payload.

T

F

5. Authentication must be applied to the entire original IP packet.

T

F

6. An end user whose system is equipped with IP security protocols can make a local call to an ISP and gain secure access to a company network.

T

F

7. Both tunnel and transport modes can be accommodated by the encapsulating security payload encryption format.

T

F

8. An individual SA can implement both the AH and the ESP protocol.

T

F

9. By implementing security at the IP level an organization can ensure secure networking not only for applications that have security mechanisms but also for the many security ignorant applications.

T

F

10. IPSec can guarantee that all traffic designated by the network administrator is authenticated but cannot guarantee that it is encrypted.

T

F

11. Any traffic from the local host to a remote host for purposes of an IKE exchange bypasses the IPsec processing.

T

F

12. IPsec is executed on a packet-by-packet basis.

T

F

13. The Payload Data Field is designed to deter replay attacks.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. The Security Parameters Index identifies a security association.

T

F

15. The default automated key management protocol for IPsec is referred to as ISAKMP/Oakley.

MULTIPLE CHOICE 1. Authentication applied to the entire original IP packet is _________ .

A) security mode

B) cipher mode

C) tunnel mode

D) transport mode

2. _________ defines a number of techniques for key management.

A) KEP

B) KMP

C) SKE

D) IKE

3. Authentication applied to all of the packet except for the IP header is _________ .

A) tunnel mode

B) transport mode

C) association mode

D) security mode

4. The __________ mechanism assures that a received packet was in fact transmitted by the party identified as the source in the packet header and assures that the packet has not been altered in transit.

A) confidentiality

B) authentication

C) security

D) key management

5. __________ provides the capability to secure communications across a LAN, across private and public WANs, and across the Internet.

A) IKE

B) ISA

C) IAB

D) IPsec

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. The _________ facility enables communicating nodes to encrypt messages to prevent eavesdropping by third parties.

A) security

B) key management

C) authentication

D) confidentiality

7. The key management mechanism that is used to distribute keys is coupled to the authentication and privacy mechanisms only by way of the _________ .

A) IAB

B) SPI

C) ESP

D) SPD

8. A _________ is a one way relationship between a sender and a receiver that affords security services to the traffic carried on it.

A) SAD

B) SPD

C) SA

D) SPI

9. The means by which IP traffic is related to specific SAs is the _________ .

A) TRS

B) SPD

C) SAD

D) SPI

10. _________ consists of an encapsulating header and trailer used to provide encryption or combined encryption/authentication. The current specification is RFC 4303.

A) SPI

B) ESP

C) ISA

D) IPsec

11. _________ identifies the type of data contained in the payload data field by identifying the first header in that payload.

A) Security Parameters Index

B) Next Header

C) Sequence Header

D) Payload Data

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

12. A value chosen by the responder to identify a unique IKE SA is a _________ .

A) Initiator SPI

B) Responder Cookie

C) Flag

D) Message ID

13. IKE key determination employs __________ to ensure against replay attacks.

A) cookies

B) groups

C) flags

D) nonces

14. The __________ payload contains either error or status information associated with this SA or this SA negotiation.

A) Encrypted

B) Notify

C) Configuration

D) Nonce

15. The _________ payload allows peers to identify packet flows for processing by IPsec services.

A) Configuration

B) Vendor ID

C) Traffic Selector

D) Extensible Authentication Protocol

SHORT ANSWER 1. IPsec encompasses three functional areas: authentication, key management, and __________ .

2. _________ mode is used when one or both ends of an SA are a security gateway, such as a firewall or router that implements IPsec.

3. IPsec policy is determined primarily by the interaction of two databases: The security policy database and the __________ .

4. Confidentiality is provided by an encryption format known as __________ .

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. A __________ attack is one in which an attacker obtains a copy of an authenticated packet and later transmits it to the intended destination.

6. Authentication makes use of the _________ message authentication code.

7. A security association is uniquely identified by three parameters: Security Protocol Identifier, IP Destination Address, and ________ .

8. The __________ facility is concerned with the secure exchange of keys.

9. _________ can be used to provide confidentiality, data origin authentication, connectionless integrity, an anti-replay service, and traffic flow confidentiality.

10. IPsec provides security services at the ________ layer by enabling a system to select required security protocols, determine the algorithms to use for the services and put in place any cryptographic keys required to provide the requested services.

11. The selectors that determine a Security Policy Database are: Name, Local and Remote Ports, Next Layer Protocol, Remote IP Address, and _________ .

12. The term _________ refers to a sequence of SAs through which traffic must be processed to provide a desired set of IPsec services.

13. Generic in that it does not dictate specific formats, the _________ is a key exchange protocol based on the Diffie-Hellman algorithm with added security.

14. Three different authentication methods can be used with IKE key determination: Public key encryption, symmetric key encryption, and _________ .

15. At any point in an IKE exchange the sender may include a _________ payload to request the certificate of the other communicating entity.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

Chapter 21 – Malicious Software Answer Key

TRUE/FALSE QUESTIONS: 1. T 2. F 3. F 4. T 5. F 6. T 7. T 8. F 9. T 10. T 11. T 12. T 13. F 14. T 15. T

MULTIPLE CHOICE QUESTIONS: 1. C 2. B 3. A 4. B 5. C 6. D 7. D 8. A 9. C 10. B 11. A 12. B 13. C 14. D 15. B

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER QUESTIONS: 1. rootkit 2. blended attack 3. virus 4. infection mechanism 5. trigger 6. propagation 7. triggering 8. stealth 9. Mobile 10. drive-by-download 11. botnet 12. keylogger 13. anti-virus 14. polymorphic virus 15. awareness

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

Chapter 21 – Malicious Software

TRUE/FALSE QUESTIONS:

T

F

1. Malicious software aims to trick users into revealing sensitive personal information.

T

F

2. Keyware captures keystrokes on a compromised system.

T

F

3. Metamorphic code is software that can be shipped unchanged to a heterogeneous collection of platforms and execute with identical semantics.

T

F

4. A virus that attaches to an executable program can do anything that the program is permitted to do.

T

F.

5. It is not possible to spread a virus via a USB stick.

T

F

6. A logic bomb is the event or condition that determines when the payload is activated or delivered.

T

F

7. Many forms of infection can be blocked by denying normal users the right to modify programs on the system.

T

F

8. A macro virus infects executable portions of code.

T

F

9. E-mail is a common method for spreading macro viruses.

T

F

10. In addition to propagating, a worm usually carries some form of payload.

T

F

11. A Trojan horse is an apparently useful program containing hidden code that, when invoked, performs some harmful function.

T

F

12. Packet sniffers are mostly used to retrieve sensitive information like usernames and passwords.

T

F

13. A bot propagates itself and activates itself, whereas a worm is initially controlled from some central facility.

T

F

14. Every bot has a distinct IP address.

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Cryptography and Network Security: Principles and Practice, 7th Edition, by William Stallings

T

F

15. DDoS attacks make computer systems inaccessible by flooding servers with useless traffic so that legitimate users can no longer gain access to those resources.

MULTIPLE CHOICE QUESTIONS:

1. A program that is covertly inserted into another program with the intent of compromising the integrity or confidentiality of the victim’s data is __________.

A. Adobe

B. Animoto

C. malware

D. Prezi

2. __________ are used to send large volumes of unwanted e-mail.

A. Rootkits

B. Spammer programs

C. Downloaders

D. Auto-rooters

3. A __________ is a program inserted into software that lies dormant until a predefined condition, which triggers an unauthorized act, is met.

A. logic bomb

B. trapdoor

C. worm

D. Trojan horse

4. A simple example of a(n) __________ attack is the SYN flood attack.

A. data consumption

B. internal resource

C. reflector DDoS

D. indirect DDoS

5. Advertising that is integrated into software is called __________ .

A. flooders

B. spyware

C. adware

D. downloaders

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

6. The __________ is what the virus “does”.

A. infection mechanism

B. trigger

C. logic bomb

D. payload

7. The __________ is when the virus function is performed.

A. dormant phase

B. propagation phase

C. triggering phase

D. execution phase

8. During the __________ the virus is idle.

A. dormant phase

B. propagation phase

C. triggering phase

D. execution phase

9. A __________ infects files with macro or scripting code that is interpreted by an application.

A. boot sector infector

B. file infector

C. macro virus

D. multipartite virus

10. __________ is the first function in the propagation phase for a network worm.

A. Propagating

B. Fingerprinting

B. Keylogging

D. Spear phishing

11. Unsolicited bulk e-mail is referred to as __________.

A. spam

B. propagating

C. phishing

D. crimeware

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Cryptography and Network Security: Principles and Practice, 7th Edition, by William Stallings

12. __________ is malware that encrypts the user’s data and demands payment in order to access the key needed to recover the information.

A. Trojan horse

B. Ransomware

C. Crimeware

D. Polymorphic

13. A __________ attack is a bot attack on a computer system or network that causes a loss of service to users.

A. spam

B. phishing

C. DDoS

D. sniff

14. The ideal solution to the threat of malware is __________.

A. identification

B. removal

C. detection

D. prevention

15. __________ will integrate with the operating system of a host computer and monitor program behavior in real time for malicious actions.

A. Fingerprint-based scanners

B. Behavior-blocking software

C. Generic decryption technology

D. Heuristic scanners

SHORT ANSWER QUESTIONS: 1. A _________ is a set of programs installed on a system to maintain covert access to that system with administrator (root) privileges while hiding evidence of its presence.

2. A __________ uses multiple methods of infection or propagation to maximize the speed of contagion and the severity of the attack.

3. A computer __________ is a piece of software that can “infect” other programs or any type of executable content and tries to replicate itself.

4. Referred to as the “infection vector”, the __________ is the means by which a virus spreads or propagates. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. Sometimes known as a “logic bomb”, the __________ is the event or condition that determines when the payload is activated or delivered.

6. The four phases of a typical virus are: dormant phase, triggering phase, execution phase and __________ phase.

7. During the __________ phase the virus is activated to perform the function for which it was intended.

8. A __________ virus is explicitly designed to hide itself from detection by anti-virus software.

9. __________ code refers to programs that can be shipped unchanged to a heterogeneous collection of platforms and execute with identical semantics.

10. A __________ is when a user views a Web page controlled by the attacker that contains a code that exploits the browser bug and downloads and installs malware on the system without the user’s knowledge or consent.

11. A __________ is a collection of bots capable of acting in a coordinated manner.

12. An attacker can install a __________ to capture keystrokes on the infected machine to retrieve sensitive information.

13. Countermeasures for malware are generally known as _________ mechanisms because they were first developed to specifically target virus infections.

14. A _________ is a form of virus that creates copies during replication that are functionally equivalent but have distinctly different bit patterns, in order to defeat programs that scan for viruses.

15. SP 800-83 lists four main elements of prevention: policy, __________ , threat mitigation, and vulnerability mitigation.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 22: INTRUDERS ANSWER KEY

TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T F T F T T T F T F T T F T F

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

D D C B B C A C D B B D A B B

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

Intrusion detection Statistical anomaly Clandestine user Access control interval timer Intrusion detection Native Rule-based honeypots IETF Intrusion Detection Working Group reactive password checking audit Counter Rule-based penetration Bayes' theorem

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 11: INTRUDERS TRUE OR FALSE T

F

1. Unauthorized intrusion into a computer system or network is one of the most serious threats to computer security.

T

F

2. Trojan horses and viruses are confined to network based attacks.

T

F

3.

T

F

4. Statistical approaches attempt to define proper behavior and rulebased approaches attempt to define normal or expected behavior.

T

F

5.

T

F

6. One important element of intrusion prevention is password management.

T

F

7.

The ID determines the privileges accorded to the user.

T

F

8.

Insider attacks are among the easiest to detect and prevent.

T

F

9. The hacking community is a strong meritocracy in which status is determined by level of competency.

T

F

10.

T

F

11. A weakness of the IDES approach is its lack of flexibility.

T

F

12. To be of practical use an intrusion detection system should detect a substantial percentage of intrusions while keeping the false alarm rate at an acceptable level.

T

F

13. System administrators can stop all attacks and hackers from penetrating their systems by installing software patches periodically.

T

F

14. Password crackers rely on the fact that some people choose easily guessable passwords.

Intrusion detection involves detecting unusual patterns of activity or patterns of activity that are known to correlate with intrusions.

The main advantage of the use of statistical profiles is that a prior knowledge of security flaws is not required.

Penetration identification is an approach developed to detect deviation from previous usage patterns.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

15.

Traditional hackers usually have specific targets, or at least classes of targets in mind.

MULTIPLE CHOICE 1. Software trespass can take the form of a _________ .

A) virus

B) worm

C) Trojan horse

D) all of the above

2. A _________ is an individual who is not authorized to use the computer and who penetrates a system's access controls to exploit a legitimate user's account.

A) sniffer C) clandestine user

B) misfeasor D) masquerader

3. _________ involves counting the number of occurrences of a specific event type over an interval of time.

A) Rule-based detection

B) Resource usage

C) Threshold detection

D) Profile-based system

4. A ________ is a legitimate user who accesses data, programs, or resources for which such access is not authorized, or who is authorized for such access but misuses his or her privileges.

A) clandestine user C) emissary

B) misfeasor D) masquerader

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. The simplest statistical test is to measure the _________ of a parameter over some historical period, which would give a reflection of the average behavior and its variability.

A. multivariate

B. mean and standard deviation

C. time series

D. Markov process

6. _________ detection focuses on characterizing the past behavior of individual users or related groups of users and then detecting significant deviations.

A. Action condition

B. Threshold

C. Profile-based anomaly

D. Statistical anomaly

7. A ________ is an individual who seizes supervisory control of the system and uses this control to evade auditing and access controls or to suppress audit collection.

A. clandestine user C. masquerader

B. misfeasor D. mole

8. The _________ model is used to establish transition probabilities among various states, such as looking at transitions between certain commands.

A. multivariate C. Markov process

B. profile-based D. operational

9. The _________ is based on a judgment of what is considered abnormal rather than an automated analysis of past audit records.

A. Markov process C. time series

B. mean and standard deviation D. operational model

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

10. The ________ is an audit collection module operating as a background process on a monitored system whose purpose is to collect data on security related events on the host and transmit these to the central manager.

A. central manager module

B. host agent module

C. intruder alert module

D. LAN monitor agent module

11. The _________ prevents duplicate passwords from being visible in the password file. If two users choose the same password, those passwords will be assigned at different times.

A. honeypot

B. salt

C. audit record

D. rule based intrusion detection

12. An operation such as login, read, perform, I/O or execute that is performed by the subject on or with an object is the _________ audit record field.

A. resource-usage C. object

B. subject D. action

13. A ________ is used to measure the current value of some entity. Examples include the number of logical connections assigned to a user application and the number of outgoing messages queued for a user process.

A. gauge

B. interval timer

C. resource utilization

D. counter

14. A ________ model is based on correlations between two or more variables.

A. mean and standard deviation

B. multivariate

C. Markov process

D. operational

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

15. The most promising approach to improved password security is __________ .

A. user education B. a proactive password checker C. computer generated passwords D. a reactive password checking strategy SHORT ANSWER 1. __________ systems have been developed to provide early warning of an intrusion so that defensive action can be taken to prevent or minimize damage.

2. _________ detection involves the collection of data relating to the behavior of legitimate users over a period of time. Statistical tests are applied to observed behavior to determine with a high level of confidence whether that behavior is not legitimate user behavior.

3. The three classes of intruders identified by Anderson are: Masquerader, Misfeasor, and _________ .

4. Password files can be protected in one of two ways: one-way function or __________ .

5. Metrics that are useful for profile-based intrusion detection are: counter, gauge, resource utilization, and _________ .

6. _________ is based on the assumption that the behavior of the intruder differs from that of a legitimate user in ways that can be quantified.

7. Two types of audit records used are Detection-specific audit records and _________ audit records.

8. _________ techniques detect intrusion by observing events in the system and applying a set of rules that lead to a decision regarding whether a given pattern of activity is or is not suspicious.

9. Designed to lure a potential attacker away from critical systems ____________ are decoy systems that divert an attacker from accessing critical systems, collect information about the hacker's activity, and encourage the attacker to stay on the system long enough for administrators to respond.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

10. The focus of the __________ is to define data formats and exchange procedures for sharing information of interest to intrusion detection and response systems and to management that may need to interact with them.

11. A _________ strategy is one in which the system periodically runs its own password cracker to find guessable passwords.

12. A fundamental tool for intrusion detection is the _________ record.

13. An example of a metric used for profile-based intrusion detection is _________ which is a non-negative integer that may be incremented but not decremented until it is reset by management action. Examples include the number of logins by a single user during an hour, the number of times a given command is executed during a single user session, and the number of password failures during a minute.

14. _________ identification takes a very different approach to intrusion detection. The key feature of such systems is the use of rules for identifying known penetration or penetrations that would exploit known weaknesses. Typically the rules used in these systems are specific to the machine and operating system.

15. One of the most important results from probability theory is known as ________ , which is used to calculate the probability that something really is the case, given evidence in favor of it.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 12: FIREWALLS ANSWER KEY

TRUE OR FALSE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

T T F T F T T F T F T F T T F

MULTIPLE CHOICE 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

C D C C B D D B B D C B B D C

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

firewall behavior double bastion inline forward source routing distributed application proxy stateful inspection circuit level gateway bastion host personal DMZ (demilitarized zone) virtual private network (VPN) Host resident single bastion inline

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

CHAPTER 12: FIREWALLS TRUE OR FALSE T

F

1. A firewall may be designed to operate as a filter at the level of IP packets or may operate at a higher protocol layer.

T

F

2. The packet filter is typically set up as a list of rules based on matches to fields in the IP or TCP header.

T

F

3.

T

F

4. The firewall cannot fully protect against internal threats.

T

F

5.

T

F

6. A stateful packet inspection firewall reviews the same packet information as a packet filtering firewall but also records information about TCP connections.

T

F

7.

One advantage of a packet filtering firewall is its simplicity.

T

F

8.

Packet filter firewalls examine upper layer data therefore they can prevent attacks that employ application specific vulnerabilities or functions.

T

F

9. Due to the small number of variables used in access control decisions packet filter firewalls are susceptible to security breaches caused by improper configurations.

T

F

10.

T

F

11. A circuit level proxy can be a stand alone system or it can be a specialized function performed by an application level gateway for certain applications.

T

F

12. An example of application level gateway implementation is the SOCKS package.

T

F

13. Firewall functionality can also be implemented as a software module in a router or LAN switch.

The direction control determines the types of Internet services that can be accessed, inbound or outbound.

A firewall may not act as a packet filter.

Packet filters tend to be more secure than application level gateways.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

T

F

14. The primary role of the personal firewall is to deny unauthorized remote access to the computer.

T

F

15.

The external firewall adds more stringent filtering capability in order to protect enterprise servers and workstations from external attack.

MULTIPLE CHOICE 1. _________ can be an effective means of protecting a local system or network of systems from network based security threats while at the same time affording access to the outside world via wide area networks and the Internet.

A. VPNs

B. Proxys

C. Firewalls

D. SOCKS

2. The _________ is the address of the system that originated the IP packet.

A. Interface B. Source and destination transport level address C. IP protocol field D. Source IP address 3. The technique that controls how particular services are used is the _________ control.

The firewall may filter e-mail to eliminate spam, or it may enable external access to only a portion of the information on a local Web server.

A. direction

B. user

C. behavior

D. service

4. The _________ is the transport level port number which defines applications such as SNMP or TELNET. A. Source IP address

B. IP protocol field

C. Source and destination transport level address

D. Interface

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. A _________ firewall applies a set of rules to each incoming and outgoing IP packet and then forwards or discards the packet.

A. host-based

B. packet filtering

C. distributed

D. stateful inspection

6. The __________ defines the transport protocol.

A. source IP address

B. destination IP address

C. interface

D. IP protocol field

7. The _________ attack is designed to circumvent filtering rules that depend on TCP header information.

A. source routing

B. IP address spoofing

C. network layer address spoofing

D. tiny fragment

8. A typical use of a _________ is a situation in which the system administrator trusts the internal users.

A. packet filtering firewall C. application level gateway

B. circuit level gateway D. stateful inspection firewall

9. SOCKS is defined in _________ as "a framework for client server applications in both the TCP and UDP domains to conveniently and securely use the services of a network firewall".

A. RFC 1935

B. RFC 1928

C. RFC 1046

D. RFC 1024

10. Available in many operating systems or provided as an add on package, a ________ is a software module used to secure an individual host and also filters and restricts the flow of packets.

A. application level gateway

B. circuit level gateway

C. host based firewall

D. DMZ

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

11. An important aspect of a distributed firewall configuration is _________ .

A. change control

B. network frame locking

C. security monitoring

D. configuration alerting

12. A ________ is a single router between internal and external networks with stateless or full packet filtering. This arrangement is typical for SOHO applications.

A. DMZ

B. screening router

C. single bastion T

D. host resident firewall

13. Common for large businesses and government organizations, the ________ configuration is required for Australian government use.

A. Double bastion inline

B. Double bastion T

C. Single bastion inline

D. Single bastion T

14. ________ has a third network interface on bastion to a DMZ where externally visible servers are placed. This is a common appliance configuration for medium to large organizations.

A. Double bastion inline

B. Double bastion T

C. Single bastion inline

D. Single bastion T

15. The iTunes Music Sharing inbound service is port number ________ .

A. 5297

B. 3031

C. 3869

D. 5298

SHORT ANSWER 1. A _________ forms a barrier through which the traffic going in each direction must pass and dictates which traffic is authorized to pass.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

2. The four general techniques that firewalls use to control access and enforce the site's security policy are: service control, direction control, user control, and __________ control.

3. Common for large businesses and government organizations, the _________ configuration sandwiches the DMZ between bastion firewalls.

4. The default _________ policy increases ease of use for end users but provides reduced security because the security administrator must, in essence, react to each new security threat as it becomes known.

5. A __________ attack is where the source station specifies the route that a packet should take as it crosses the Internet in the hopes that this will bypass security measures that do not analyze the source routing information.

6. A _________ firewall configuration involves stand alone firewall devices plus host based firewalls working together under a central administrative control.

7. Four types of firewalls are: Packet filtering, stateful inspection, circuit level proxy and _________ .

8. A _________ packet firewall tightens up the rules for TCP traffic by creating a directory of outbound TCP connections. There is an entry for each currently established connection and the packet filter will now allow incoming traffic to high numbered ports only for those packets that fit the profile of one of the entries in this directory.

9. A _________ sets up two TCP connections, one between itself and a TCP user on an inner host and one between itself and a TCP user on an outside host. Once the two connections are established TCP segments from one connection are relayed to the other without examining the contents.

10. Typically serving as a platform for an application level or circuit level gateway, a ________ is a system identified by the firewall administrator as a critical strong point in the network's security.

11. A ________ firewall controls the traffic between a personal computer or workstation on one side and the Internet or enterprise network on the other side.

12. Between an internal firewall and an external firewall are one or more networked devices in a region referred to as a _________ . Systems that are externally accessible but need some protection are usually located in this area.

13. A _________ consists of a set of computers that interconnect by means of a relatively unsecure network and that make use of encryption and special protocols to provide security. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

14. _________ firewalls include personal firewall software and firewall software on servers. Such firewalls can be used alone or as part of an in-depth firewall deployment.

15. A ________ is a single firewall device between an internal and external router. The firewall may implement stateful filters and/or application proxies. This is the typical firewall appliance configuration for small to medium sized organizations.

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

Chapter 24 – Legal and Ethical Aspects Answer Key

TRUE/FALSE QUESTIONS: 1. T 2. F 3. T 4. T 5. T 6. F 7. F 8. T 9. T 10. T 11. T 12. F 13. T 14. T 15. T MULTIPLE CHOICE QUESTIONS: 1. A 2. B 3. A 4. C 5. C 6. D 7. D 8. A 9. C 10. B 11. B 12. D 13. A 14. C 15. B

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

SHORT ANSWER QUESTIONS: 1. Computer crime 2. Convention on Cybercrime 3. intellectual 4. trademarks 5. infringement 6. IP owner 7. plant patents 8. utility patent 9. Trademark 10. clearinghouse 11. Children’s Online Privacy Protection 12. pseudonymity 13. Ethics 14. Fair Credit Reporting Act 15. technical

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Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

Chapter 24 – Legal and Ethical Aspects

TRUE/FALSE QUESTIONS:

T

F

1. The legal and ethical aspects of computer security encompass a broad range of topics.

T

F

2. Computer attacks are considered crimes but do not carry criminal sanctions.

T

F

3. “Computers as targets” is a form of crime that involves an attack on data integrity, system integrity, data confidentiality, privacy, or availability.

T

F

4. The relative lack of success in bringing cybercriminals to justice has led to an increase in their numbers, boldness, and the global scale of their operations.

T

F

5. No cybercriminal databases exist that can point investigators to likely suspects.

T

F

6. The successful use of law enforcement depends much more on technical skills than on people skills.

T

F

7. Software is an example of real property.

T

F

8. An example of a patent from the computer security realm is the RSA public-key cryptosystem.

T

F

9. A servicemark is the same as a trademark except that it identifies and distinguishes the source of a service rather than a product.

T

F

10. Concerns about the extent to which personal privacy has been and may be compromised have led to a variety of legal and technical approaches to reinforcing privacy rights.

T

F

11. The purpose of the privacy functions is to provide a user protection against discovery and misuse of identity by other users.

T

F

12. The Common Criteria specification is primarily concerned with the privacy of personal information concerning the individual rather than the privacy of an individual with respect to that individual’s use of computer resources. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, by William Stallings

T

F

13. Computer technology has involved the creation of new types of entities for which no agreed ethical rules have previously been formed.

T

F

14. Anyone can join the Ad Hoc Committee on Responsible Computing.

T

F

15. The first comprehensive privacy legislation adopted in the United States was the Privacy Act of 1974.

MULTIPLE CHOICE QUESTIONS:

1. _______ is a form of crime that targets a computer system to acquire information stored on that computer system, to control the target system without authorization or payment, or to alter the integrity of data or interfere with the availability of the computer or server.

A. Computers as targets

B. Computers as storage devices

C. Computers as mediums

D. Computers as communication tools

2. The success of cybercriminals, and the relative lack of success of law enforcement, influence the behavior of _______.

A. cyber thieves

B. cybercrime victims

C. cybercrime acts

D. cyber detectives

3. Land and things permanently attached to the land, such as trees, buildings, and stationary mobile homes are _______.

A. real property

B. cyber property

C. personal property

D. intellectual property

4. Personal effects, moveable property and goods, such as cars, bank accounts, wages, securities, a small business, furniture, insurance policies, jewelry, patents, and pets are all examples of _________.

A. intellectual property

B. real property

C. personal property

D. cyber property

5. Any intangible asset that consists of human knowledge and ideas is _______. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

A. cyber property

B. personal property

C. intellectual property

D. real property

6. _____ can be copyrighted.

A. Dramatic works

B. Architectural works

C. Software-related works

D. All of the above

7. The copyright owner has which exclusive right(s)?

A. reproduction right

B. distribution right

C. modification right

D. all of the above

8. A _______ for an invention is the grant of a property right to the inventor.

A. patent

B. copyright

C. trademark

D. claim

9. A ______ is a word, name, symbol, or device that is used in trade with goods to indicate the source of the goods and to distinguish them from the goods of others.

A. copyright

B. patent

C. trademark

D. all of the above

10. _____ strengthens the protection of copyrighted materials in digital format.

A. HIPPA

B. DMCA

C. WIPO

D. DRM

11. A ________ provides distribution channels, such as an online shop or a Web retailer.

A. content provider

B. distributor

C. consumer

D. clearinghouse

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Cryptography and Network Security: Principles and Practice, 7th Edition, by William Stallings

12. ________ ensures that a user may make multiple uses of resources or services without others being able to link these uses together.

A. Anonymity

B. Pseudonymity

C. Unobservability

D. Unlinkability

13. ________ is a function that removes specific identifying information from query results, such as last name and telephone number, but creates some sort of unique identifier so that analysts can detect connections between queries.

A. Anonymization

B. Data transformation

C. Immutable audit

D. Selective revelation

14. ______ is intended to permit others to perform, show, quote, copy, and otherwise distribute portions of the work for certain purposes.

A. Reverse engineering

B. Personal privacy

C. Fair use

D. Encryption research

15. ________ is a method for minimizing exposure of individual information while enabling continuous analysis of potentially interconnected data.

A. Immutable audit

B. Selective revelation

C. Associative memory

D. Anonymization

SHORT ANSWER QUESTIONS:

1. _______ or cybercrime, is a term used broadly to describe criminal activity in which computers or computer networks are a tool, a target, or a place of criminal activity.

2. The 2001 _________ is the first international treaty seeking to address Internet crimes by harmonizing national laws, improving investigative techniques, and increasing cooperation among nations.

3. The U.S. legal system distinguishes three primary types of property: real property, personal property, and _________ property.

4. The three main types of intellectual property for which legal protection is available are: copyrights, patents, and _______. © 2017 Pearson Education, Ltd. All rights reserved.

Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition, by William Stallings

5. The invasion of the rights secured by patents, copyrights, and trademarks is ________.

6. The right to seek civil recourse against anyone infringing his or her property is granted to the ________.

7. The three types of patents are: utility patents, design patents, and ________.

8. A(n) _________ may be granted to anyone who invents or discovers any new and useful process, machine, article of manufacture, or composition of matter, or any new and useful improvement thereof.

9. ________ rights may be used to prevent others from using a confusingly similar mark, but not to prevent others from making the same goods or from selling the same goods or services under a clearly different mark.

10. A ______ handles the financial transaction for issuing the digital license to the consumer and pays royalty fees to the content provider and distribution fees to the distributor accordingly.

11. The ___________ Act places restrictions on online organizations in the collection of data from children under the age of 13.

12. Privacy is broken down into four major areas: anonymity, unlinkability, unobservability, and _________.

13. _______ refers to a system of moral principles that relates to the benefits and harms of particular actions, and to the rightness and wrongness of motives and ends of those actions.

14. The _________ Act confers certain rights on individuals and obligations on credit reporting agencies.

15. Both policy and ________ approaches are needed to protect privacy when both government and nongovernment organization seek to learn as much as possible about individuals.

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