MIS 8th Edition By Bidgoli - Test Bank

MIS 8th Edition By Bidgoli – Test Bank

 

Instant Download – Complete Test Bank With Answers

 

 

Sample Questions Are Posted Below

 

Indicate whether the statement is true or false.

1. In some instances, after examining an incoming packet, a firewall can send a message to the packet’s sender that the attempt to transmit the packet has failed.
a. True
b. False

2. Viruses can be transmitted through a network or through e-mail attachments.
a. True
b. False

3. The cost of setting up a virtual private network (VPN) is usually high.
a. True
b. False

4. When using mirror disks, if one of the two disks containing the same data fails, the other disk also fails.
a. True
b. False

5. An intrusion detection system (IDS) can protect networks against both external and internal access.
a. True
b. False

6. The main drawback of an intrusion detection system (IDS) is its inability to prevent denial-of-service (DoS) attacks.
a. True
b. False

7. Terminal resource security is a software feature that erases the screen and signs a user off automatically after a specified length of inactivity.
a. True
b. False

8. When disaster strikes, an organization should contact the insurance company to resume normal operations as soon as possible.
a. True
b. False

9. Application-filtering firewalls are less expensive than packet-filtering firewalls.
a. True
b. False

10. When a program containing a virus is used, the virus attaches itself to other files, and the cycle continues.
a. True
b. False

11. If a drive in a redundant array of independent disks (RAID) system fails, data stored on it can be reconstructed from data stored on the remaining drives.
a. True
b. False

12. In contrast to pharming, phishing involves hijacking an official Web site address by hacking a Domain Name System server.
a. True
b. False

13. Auction fraud is sending fraudulent e-mails that seem to come from legitimate sources, such as a bank or university.
a. True
b. False

14. In the context of the CIA triangle, confidentiality means that computers and networks are operating and authorized users can access the information they need.
a. True
b. False

15. In the context of intentional computer and network threats, social engineers protects the integrity of information resources.
a. True
b. False

16. Social engineering is an attack that takes advantage of the backdoors in security systems.
a. True
b. False

17. Level 1 security protects back-end systems to ensure confidentiality, accuracy, and integrity of data.
a. True
b. False

18. When an organization develops a comprehensive security plan, it should set up a security committee with representatives from all departments as well as upper management.
a. True
b. False

19. The three important aspects of computer and network security, confidentiality, integrity, and availability, are collectively referred to as the CIA triangle.
a. True
b. False

Indicate the answer choice that best completes the statement or answers the question.

20. In the context of computer and network security, _____ means that computers and networks are operating and authorized users can access the information they need.
a. validity
b. confidentiality
c. integrity
d. availability

21. Keystroke loggers
Correct
Key chain planners
Incorrect
Key punchers
Incorrect
Key performers
Incorrect
monitor and record the keys pressed on a keyboard and can be software or hardware devices.
a. Keystroke loggers
b. Key chain planners
c. Key punchers
d. Key performers

22. _____, a recent cryptographic protocol, ensures data security and integrity over public networks, such as the Internet.
a. Transport Layer Security
b. Terminal Resource Security
c. Transmission Control Security
d. User Datagram Security

23. _____ is a computer crime that involves destroying or disrupting computer services.
a. Sabotage
b. Dumpster diving
c. Bombing
d. Keystroke logging

24. In a level 2 security system, _____ must be protected to ensure confidentiality, accuracy, and integrity of data.
a. back-end systems
b. external databases
c. private networks
d. front-end servers

25. A level 1 security system is used to protect _____ against unauthorized access.
a. users’ workstations
b. back-end systems
c. internal database servers
d. front-end servers

26. A blended threat
Correct
magnetic threat
Incorrect
signal threat
Incorrect
router threat
Incorrect
is a security threat that may launch a worm through a Trojan horse or launch a denial-of-service attack at a targeted IP address.
a. blended threat
b. magnetic threat
c. signal threat
d. router threat

27. _____ are usually placed in front of a firewall and can identify attack signatures, trace patterns, generate alarms for a network administrator, and cause routers to terminate connections with suspicious sources.
a. Intrusion detection systems
b. Proxy servers
c. Identification badges
d. Virtual private networks

28. Which of the following statements is true of firewalls?
a. They protect against external access, but they leave networks unprotected from internal intrusions.
b. They can identify attack signatures, trace patterns, and generate alarms for a network administrator.
c. They monitor network traffic and use the “prevent, detect, and react” approach to security.
d. They cause routers to terminate connections with suspicious sources.

29. In the context of computer crimes and attacks, the difference between phishing and spear phishing is that:
a. in spear phishing, the attack is targeted toward a specific person or a group.
b. spear phishing involves monitoring and recording keystrokes.
c. in spear phishing, hackers capture and record network traffic.
d. spear phishing involves collecting sensitive information via phone calls.

30. In data encryption, the https in a browser address bar indicates a safe HTTP connection over _____.
a. Secure Sockets Layer
b. Transport Layer Security
c. User Datagram Protocol
d. Transmission Control Protocol

31. Which of the following is a biometric security measure?
a. Terminal resource security
b. A corner bolt
c. A callback modem
d. Signature analysis

32. _____ can interfere with users’ control of their computers, through such methods as installing additional software and redirecting Web browsers.
a. Keystroke loggers
b. Spyware
c. Firmware
d. Script loggers

33. Which of the following is a type of access control used to protect systems from unauthorized access?
a. Electronic trackers
b. Passwords
c. Firewalls
d. Identification badges

34. In the context of the common intentional security threats, which of the following statements best describes a worm?
a. It travels from computer to computer in a network, but it does not usually erase data.
b. It attaches itself to a host program to spread to other files in a computer.
c. It is a programming routine built into a system by its designer to bypass system security and sneak back into the system later to access data.
d. It floods a network or server with service requests to prevent legitimate users’ access to the system.

35. Similar to phishing, _____ is directing Internet users to fraudulent Web sites with the intention of stealing their personal information, such as Social Security numbers, passwords, bank account numbers, and credit card numbers.
a. sniffing
b. screening
c. pharming
d. cybersquatting

36. In the context of intentional security threats, _____ can erase data and wreak havoc on computers and networks but do not replicate themselves.
a. Trojan programs
b. worms
c. viruses
d. McCumber cubes

37. Dashlane
Correct
STOPzilla
Incorrect
CounterSpy
Incorrect
FilePro
Incorrect
is one of the most popular password managers.
a. Dashlane
b. STOPzilla
c. CounterSpy
d. FilePro

38. Code Red, Melissa, and Sasser are examples of worms
Correct
firewalls
Incorrect
cable shields
Incorrect
corner bolts
Incorrect
.
a. worms
b. firewalls
c. cable shields
d. corner bolts

39. In the context of intentional computer and network threats, a _____ combines the characteristics of computer viruses, worms, and other malicious codes with vulnerabilities found on public and private networks.
a. blended threat
b. mirror disk
c. backdoor threat
d. firewall

40. Which of the following intentional computer and network threats is a type of Trojan program used to release a virus, worm, or other destructive code?
a. A logic bomb
b. Dumpster diving
c. A blended threat
d. Shoulder surfing

41. _____ uses a public key known to everyone and a private key known only to the recipient.
a. Symmetric encryption
b. Asymmetric encryption
c. Remote key encryption
d. Secret key encryption

42. Which of the following statements is true of application-filtering firewalls?
a. They are less secure than packet-filtering firewalls.
b. They filter viruses less effectively than packet-filtering firewalls.
c. They filter faster than packet-filtering firewalls.
d. They are more expensive than packet-filtering firewalls.

43. In the context of computer and network security, _____ means that a system must not allow the disclosing of information by anyone who is not authorized to access it.
a. reliability
b. confidentiality
c. integrity
d. availability

44. Which of the following statements is true of a worm?
a. It is an independent program that can spread itself without attaching itself to a host program.
b. It floods a network or server with service requests to prevent legitimate users’ access to the system.
c. It is usually hidden inside a popular program, but it is not capable of replicating itself.
d. It enables a system designer to bypass the security of a system and sneak back into the system later to access files.

45. A _____ is a type of an intentional computer and network threat.
a. latch
b. proxy server
c. backdoor
d. corner bolt

46. When planning a comprehensive security system, the first step is designing fault-tolerant systems
Correct
vulnerability-evade systems
Incorrect
primary-defense systems
Incorrect
database-resilient systems
Incorrect
, which use a combination of hardware and software for improving reliability-a way of ensuring availability in case of a system failure.
a. fault-tolerant systems
b. vulnerability-evade systems
c. primary-defense systems
d. database-resilient systems

47. In the context of intentional computer and network threats, a _____ is a programming routine built into a system by its designer or programmer to bypass system security and sneak back into the system later to access programs or files.
a. logic bomb
b. proxy server
c. firewall
d. backdoor

48. In the event of a network attack or intrusion, a _____ lists the tasks that must be performed by the organization to restore damaged data and equipment.
a. risk assessment plan
b. systems engineering plan
c. disaster recovery plan
d. security compliance plan

49. Which of the following statements is true of asymmetric encryption?
a. It uses the same key to encrypt and decrypt a message.
b. It requires a large amount of processing power.
c. It can easily share a key over the Internet.
d. It needs the shared key to be a secret between the sender and the receiver.

50. Which of the following biometric security measures compares the length of each finger, the translucence of fingertips, and the webbing between fingers against stored data to verify users’ identities?
a. Hand geometry
b. Fingerprint recognition
c. Vein analysis
d. Palm prints

51. Spoofing happens when:
a. an illegitimate program poses as a legitimate one.
b. keystrokes are monitored and recorded.
c. a word is converted into a digital pattern.
d. a firewall rejects the incoming data packets.

52. A level 3 security system focuses on protecting the _____ against intrusion, denial-of-service attacks, and unauthorized access.
a. back-end server
b. corporate network
c. user’s work station
d. front-end server

53. The main function of Cyber Incident Response Capability (CIRC) is to _____.
a. provide level 1 security
b. restrict access controls to unauthorized personnel
c. provide information on security incidents
d. create backdoors to bypass security protocols

54. In the context of computer and network security, _____ means a quick recovery in the event of a system failure or disaster.
a. availability
b. confidentiality
c. integrity
d. validity

55. The process of capturing and recording network traffic is referred to as _____.
a. sniffing
b. phishing
c. bombing
d. pharming

56. In the context of firewall as a nonbiometric security measure, a _____ is software that acts as an intermediary between two systems.
a. logic bomb
b. callback modem
c. proxy server
d. block multiplexer

57. Data sent through a virtual private network (VPN) can be encrypted using the _____.
a. User Datagram Protocol
b. Transmission Control Protocol
c. Internet Control Message Protocol
d. Layer Two Tunneling Protocol

58. Which of the following statements best describes spyware?
a. It is software that secretly gathers information about users while they browse the Web.
b. It is an attack that floods a server with service requests to prevent legitimate users’ access to the system.
c. It is encryption security that manages transmission security on the Internet.
d. It is a programming routine built into a system by its designer to bypass system security and sneak back into the system later to access programs or files.

59. The Committee on National Security Systems (CNSS) proposed a model known as the _____ for evaluating information security.
a. McCumber cube
b. Six Sigma model
c. Bohr model
d. SWOT analysis

60. Voice recognition
Correct
Audio manipulation
Incorrect
Word exhibition
Incorrect
Keyword identification
Incorrect
, a biometric security measure, translates words into digital patterns, which are recorded and examined for tone and pitch.
a. Voice recognition
b. Audio manipulation
c. Word exhibition
d. Keyword identification

61. John downloaded Alten Cleaner, a program that poses as a computer registry cleaner, on his computer. Once he installed the program on his computer, the program illegitimately gained access to John’s passwords and credit card information. In this scenario, it is evident that John was a victim of _____.
a. spoofing
b. phishing
c. baiting
d. pharming

62. _____ is a type of data encryption that enables users of the Internet to securely and privately exchange data through the use of a pair of keys that is obtained from a trusted authority and shared through that authority.
a. A public key infrastructure
b. Open key encryption
c. Secret key encryption
d. A private key infrastructure

63. _____ is also known as secret key encryption.
a. Symmetric encryption
b. Auto key generation
c. Public key cryptography
d. Message authentication

64. _____ are an inexpensive way to secure a computer to a desktop or counter and often have locks as an additional protection against theft.
a. Corner bolts
b. Identification badges
c. Callback modems
d. Electronic trackers

65. _____ primarily control access to computers and networks and include devices for securing computers and peripherals from theft.
a. Nonbiometric security measures
b. Virtual security measures
c. Biometric security measures
d. Physical security measures

66. In the context of intentional computer and network threats, a _____ floods a network or server with service requests to prevent legitimate users’ access to the system.
a. blended threat
b. denial-of-service attack
c. keystroke logging attack
d. backdoor threat

67. A virus
Correct
mirror disk
Incorrect
cable shield
Incorrect
backdoor
Incorrect
consists of self-propagating program code that is triggered by a specified time or event.
a. virus
b. mirror disk
c. cable shield
d. backdoor

68. User Datagram Protocol
Incorrect
Transmission Control Protocol
Incorrect
Transport Layer Security
Incorrect
Internet Protocol Security
Correct
is used to encrypt the data sent through a virtual private network (VPN).
a. User Datagram Protocol
b. Transmission Control Protocol
c. Transport Layer Security
d. Internet Protocol Security

69. Spoofing
Correct
Keystroke logging
Incorrect
Phishing
Incorrect
Pharming
Incorrect
is an attempt to gain access to a network by posing as an authorized user in order to find sensitive information, such as passwords and credit card information.
a. Spoofing
b. Keystroke logging
c. Phishing
d. Pharming

70. Adware
Correct
Silverware
Incorrect
Freeware
Incorrect
Hardware
Incorrect
is a form of spyware that collects information about a user (without the user’s consent) to determine which commercials to display in the user’s Web browser.
a. Adware
b. Silverware
c. Freeware
d. Hardware

71. _____ outlines procedures for keeping an organization operational in the event of a natural disaster or a network attack or intrusion.
a. An access control system
b. Business continuity planning
c. An intrusion detection system
d. Terminal resource security

72. In the context of computer and network security, _____ refers to the accuracy of information resources within an organization.
a. validity
b. confidentiality
c. integrity
d. availability

73. Which of the following is a nonbiometric security measure?
a. Electronic trackers
b. Retinal scanning
c. Callback modems
d. Signature analysis

74. Which of the following statements is true of phishing?
a. It involves monitoring and recording keystrokes.
b. It involves sending fraudulent e-mails that seem to come from legitimate sources.
c. It consists of self-propagating program code that is triggered by a specified time or event.
d. It prevents the disclosure of information to anyone who is not authorized to access it.

75. Computer fraud
Correct
Denial-of-service
Incorrect
Keystroke logging
Incorrect
Social engineering
Incorrect
is the unauthorized use of system data for personal gain, such as transferring money from another’s account or charging purchases to someone else’s account.
a. Computer fraud
b. Denial-of-service
c. Keystroke logging
d. Social engineering

76. Which of the following forms of text needs to be unscrambled using a decryption key?
a. Plaintext
b. Cleartext
c. Teletext
d. Ciphertext

77. STOPzilla
Correct
AndroZip
Incorrect
Tumblr
Incorrect
Dogpile
Incorrect
is an example of antispyware software.
a. STOPzilla
b. AndroZip
c. Tumblr
d. Dogpile

78. As a physical security measure, _____.
a. electronic trackers are attached to a computer at the power outlet
b. passwords are used to restrict access to computers
c. firewalls are used to filter data packets
d. a user’s signature is verified before granting accessibility

79. When a computer is infected by a virus, _____.
a. the system’s disk access is fast
b. system updates are recommended often
c. some programs suddenly increase in size
d. the available memory space remains constant

80. A(n) firewall
Correct
rootkit
Incorrect
intrusion detection system
Incorrect
electronic tracker
Incorrect
is a combination of hardware and software that acts as a filter or barrier between a private network and external computers or networks.
a. firewall
b. rootkit
c. intrusion detection system
d. electronic tracker

81. A(n) Trojan program
Correct
PageRank
Incorrect
exit application
Incorrect
withdrawal suite
Incorrect
contains code intended to disrupt a computer, network, or Web site and is usually hidden inside a popular program.
a. Trojan program
b. PageRank
c. exit application
d. withdrawal suite

82. A(n) _____ is often used so that remote users have a secure connection to an organization’s network.
a. biometric security network
b. intrusion detection network
c. virtual private network
d. terminal resource network

83. _____ is a commonly used encryption protocol that manages transmission security on the Internet.
a. Application Layer
b. Secure Sockets Layer
c. Transmission Control Protocol
d. User Datagram Protocol

84. In the context of security, _____ is an attack that takes advantage of the human element of security systems.
a. disk mirroring
b. weblogging
c. voice recognition
d. social engineering

85. In the context of e-commerce transaction security measures, authentication is a critical factor because it ensures that:
a. a system quickly recovers in the event of a system failure or disaster.
b. the person using a credit card number is the card’s legitimate owner.
c. the accuracy of information resources within an organization is maintained.
d. a system can easily be restored to operational status.

86. Which of the following statements is true of symmetric encryption?
a. It uses two different keys to encrypt and decrypt a message.
b. It requires more processing power than asymmetric encryption.
c. It is difficult to share a key over the Internet in symmetric encryption.
d. It is impossible to create digital signatures using symmetric encryption.

87. In the context of computer and network security, a security system is said to possess _____ when it does not allow data to be corrupted or allow unauthorized changes to a corporate database.
a. integrity
b. confidentiality
c. validity
d. availability

88. Which of the following security measures uses a physiological element that is unique to a person and cannot be stolen, lost, copied, or passed on to others?
a. A physical security measure
b. A firewall security measure
c. An e-commerce security measure
d. A biometric security measure

89. Terminal resource security
Correct
Distance-vector routing
Incorrect
Direct digital synthesis
Incorrect
Link-state routing
Incorrect
is a method of access control that prevents unauthorized users from using an unattended computer to access the network and data.
a. Terminal resource security
b. Distance-vector routing
c. Direct digital synthesis
d. Link-state routing

 

90. Briefly explain how packet-filtering firewalls work.

91. Describe how a virtual private network (VPN) works.

92. In the context of intentional computer and network threats, describe how blended threats work.

93. Briefly discuss dumpster diving and shoulder surfing, two commonly used social-engineering techniques.

94. Discuss the guidelines for improving a firewall’s capabilities.

95. Discuss the functions of the Computer Emergency Response Team (CERT).

96. In the context of fault-tolerant systems, describe uninterruptible power supply (UPS).

97. List the different types of intentional computer and network security threats.

98. Describe the three levels of security in a comprehensive security system.

99. In the context of biometric security measures, briefly describe some biometric devices and measures.

100. In the context of data encryption, briefly describe asymmetric encryption.

101. Briefly explain an intrusion detection system (IDS).

102. Briefly discuss how a worm can disrupt a computer or a network.

103. Briefly list some of the indications of a computer being infected by a virus.

104. List the actions that a firewall can take after examining a packet.

105. Explain the use of callback modems as a nonbiometric security measure.

106. Briefly discuss the process of data encryption.

107. In the context of access controls, briefly explain the guidelines that need to be followed to increase the effectiveness of passwords.

108. Explain how proximity-release door openers are used as a physical security measure to control access to computers and networks.

109. Briefly explain the McCumber cube.

Answer Key

1. True

2. True

3. False

4. False

5. True

6. False

7. True

8. True

9. False

10. True

11. True

12. False

13. False

14. False

15. False

16. False

17. False

18. True

19. True

20. d

21. a

22. a

23. a

24. a

25. d

26. a

27. a

28. a

29. a

30. a

31. d

32. b

33. b

34. a

35. c

36. a

37. a

38. a

39. a

40. a

41. b

42. d

43. b

44. a

45. c

46. a

47. d

48. c

49. b

50. a

51. a

52. b

53. c

54. a

55. a

56. c

57. d

58. a

59. a

60. a

61. a

62. a

63. a

64. a

65. d

66. b

67. a

68. d

69. a

70. a

71. b

72. c

73. c

74. b

75. a

76. d

77. a

78. a

79. c

80. a

81. a

82. c

83. b

84. d

85. b

86. c

87. a

88. d

89. a

90. Answers will vary. Packet-filtering firewalls control data traffic by configuring a router to examine packets passing into and out of a network. The router examines the following information in a packet: source IP address and port, destination IP address and port, and protocol used. Based on this information, rules called packet filters determine whether a packet is accepted, rejected, or dropped. For example, a packet filter can be set up to deny packets coming from specific IP addresses. A packet-filtering firewall informs senders if packets are rejected but does nothing if packets are dropped; senders have to wait until their requests time out to learn that the packets they sent were not received.
In addition, these firewalls record all incoming connections, and packets that are rejected might be a warning sign of an unauthorized attempt. Packet-filtering firewalls are somewhat inefficient, however, because they have to examine packets one by one, and they might be difficult to install. In addition, they cannot usually record every action taking place at the firewall, so network administrators could have trouble finding out whether and how intruders are trying to break into the network.

91. Answers will vary. A VPN provides a secure “tunnel” through the Internet for transmitting messages and data via a private network. It is often used so remote users have a secure connection to an organization’s network. VPNs can also be used to provide security for extranets, which are networks set up between an organization and an external entity, such as a supplier. Data is encrypted before it is sent through the tunnel with a protocol, such as Layer Two Tunneling Protocol or Internet Protocol Security. The cost of setting up a VPN is usually low, but transmission speeds can be slow, and lack of standardization can be a problem.
Typically, an organization leases the media used for a VPN on an as-needed basis, and network traffic can be sent over the combination of a public network (usually the Internet) and a private network. VPNs are an alternative to private leased lines or dedicated Integrated Services Digital Network (ISDN) lines and T1 lines.

92. Answers will vary. A blended threat is a security threat that combines the characteristics of computer viruses, worms, and other malicious codes with vulnerabilities found on public and private networks. Blended threats search for vulnerabilities in computer networks and then take advantage of these vulnerabilities by embedding malicious codes in the server’s HTML files or by sending unauthorized e-mails from compromised servers with a worm attachment. They may launch a worm through a Trojan horse or launch a denial-of-service attack at a targeted IP address. Their goal is not just to start and transmit an attack but to spread it.

93. Answers will vary. Two commonly used social-engineering techniques are called dumpster diving and shoulder surfing. Social engineers often search through dumpsters or trash cans looking for discarded material (such as phone lists and bank statements) that they can use to help break into a network. For example, a social engineer might look up the phone number of a receptionist he or she can call and pretend to be someone else in the organization. Shoulder surfing-that is, looking over someone’s shoulder-is the easiest form of collecting information. Social engineers use this technique to observe an employee entering a password or a person entering a PIN at an ATM, for example.

94. Answers will vary. Guidelines for improving a firewall’s capabilities include the following:
a. Identify what data must be secured, and conduct a risk analysis to assess the costs and benefits of a firewall.
b. Compare a firewall’s features with the organization’s security needs. For example, if your organization uses e-mail and FTP frequently, you must make sure that the application-filtering firewall you are considering can handle these network applications.
c. Compare features of packet-filtering firewalls, application-filtering firewalls, and proxy servers to determine which of these types addresses your network’s security needs the best.
d. Examine the costs of firewalls, and remember that the most expensive firewall is not necessarily the best. Some inexpensive firewalls might be capable of handling everything your organization needs.
e. Compare the firewall’s security with its ease of use. Some firewalls emphasize accuracy and security rather than ease of use and functionality. Determine what is most important to your organization when considering the trade-offs.
f. Check the vendor’s reputation, technical support, and update policies before making a final decision. As the demand for firewalls has increased, so has the number of vendors, and not all vendors are equal. Keep in mind that you might have to pay more for a product from a vendor with a good reputation that offers comprehensive technical support.

95. Answers will vary. The CERT was developed by the Defense Advanced Research Projects Agency (part of the Department of Defense) in response to the 1988 Morris worm attack, which disabled 10 percent of the computers connected to the Internet. Many organizations now follow the CERT model to form teams that can handle network intrusions and attacks quickly and effectively. Currently, CERT focuses on security breaches and denial-of-service (DoS) attacks and offers guidelines on handling and preventing these incidents. CERT also conducts a public awareness campaign and researches Internet security vulnerabilities and ways to improve security systems. Network administrators and e-commerce site managers should check the CERT Coordination Center for updates on protecting network and information resources.

96. Answers will vary. UPS is a backup power unit that continues to provide electrical power in the event of blackouts and other power interruptions and is most often used to protect servers. It performs two crucial tasks: It serves as a power source to continue running the server (usually for a short period), and it safely shuts down the server. More sophisticated UPS units can prevent users from accessing the server and send an alert to the network administrator.

97. Answers will vary. Intentional computer and network threats include the following:
a. Viruses
b. Worms
c. Trojan programs
d. Logic bombs
e. Backdoors
f. Blended threats (e.g., a worm launched by Trojan)
g. Rootkits
h. Denial-of-service attacks
i. Social engineering

98. Answers will vary. A comprehensive security system must provide three levels of security:
• Level 1: Front-end servers, those available to both internal and external users, must be protected against unauthorized access. Typically, these systems are e-mail and Web servers.
• Level 2: Back-end systems (such as users’ workstations and internal database servers) must be protected to ensure confidentiality, accuracy, and integrity of data.
• Level 3: The corporate network must be protected against intrusion, denial-of-service attacks, and unauthorized access.

99. Answers will vary. The following list describes some biometric devices and measures:
• Facial recognition-Identify users by analyzing the unique shape, pattern, and positioning of facial features.
• Fingerprints-Scan users’ fingerprints and verify them against prints stored in a database.
• Hand geometry-Compare the length of each finger, the translucence of fingertips, and the webbing between fingers against stored data to verify users’ identities.
• Iris analysis-Use a video camera to capture an image of the user’s iris, then use software to compare the data against stored templates.
• Palm prints-Use the palm’s unique characteristics to identify users. A palm reader uses near-infrared light to capture a user’s vein pattern, which is unique to each individual. This is compared to a database that contains existing patterns. This method is often used by law enforcement agencies.
• Retinal scanning-Scan the retina using a binocular eye camera, then check against data stored in a database.
• Signature analysis-Check the user’s signature as well as deviations in pen pressure, speed, and length of time used to sign the name.
• Vein analysis-Analyze the pattern of veins in the wrist and back of the hand without making any direct contact with the veins.
• Voice recognition-Translate words into digital patterns, which are recorded and examined for tone and pitch. Using voice to verify user identity has one advantage over most other biometric measures: It can work over long distances via ordinary telephones. A well-designed voice-recognition security system can improve the security of financial transactions conducted over the phone.

100. Answers will vary. Asymmetric encryption uses two keys: a public key known to everyone and a private or secret key known only to the recipient. A message encrypted with a public key can be decrypted only with the same algorithm used by the public key and requires the recipient’s private key, too. Anyone intercepting the message cannot decrypt it, because he or she does not have the private key.
This encryption usually works better for public networks, such as the Internet. Each company conducting transactions or sending messages gets a private key and a public key; a company keeps its private key and publishes its public key for others to use.

101. Answers will vary. Firewalls protect against external access, but they leave networks unprotected from internal intrusions. An IDS can protect against both external and internal access. It is usually placed in front of a firewall and can identify attack signatures, trace patterns, generate alarms for a network administrator, and cause routers to terminate connections with suspicious sources.
These systems can also prevent denial-of-service attacks. An IDS monitors network traffic and uses the “prevent, detect, and react” approach to security. Although it improves security, it requires a great deal of processing power and can affect network performance. It might also need additional configuration to prevent it from generating false positive alarms.

102. Answers will vary. A worm travels from computer to computer in a network, but it does not usually erase data. Unlike a virus, it is an independent program that can spread itself without having to be attached to a host program. It might corrupt data, but it usually replicates itself into a full-blown version that eats up computing resources, eventually bringing a computer or network to a halt. Well-known worms include Code Red, Melissa, and Sasser. Conficker, a recent worm, has infected millions of Windows computers.

103. Answers will vary. The following list describes some of the indications that a computer might be infected by a virus:
• Some programs have suddenly increased in size.
• Files have been corrupted, or the user is unable to open some files.
• Hard disk free space is reduced drastically.
• The keyboard locks up, or the screen freezes.
• Available memory dips down more than usual.
• Disk access is slow.
• The computer takes longer than normal to start.
• There is unexpected disk activity, such as the disk drive light flashing even though the user is not trying to save or open a file.
• There are unfamiliar messages on the screen.

104. Answers will vary. A firewall can examine data passing into or out of a private network and decide whether to allow the transmission based on users’ IDs, the transmission’s origin and destination, and the transmission’s contents. Information being transmitted is stored in what’s called a packet, and after examining a packet, a firewall can take one of the following actions:
• Reject the incoming packet.
• Send a warning to the network administrator.
• Send a message to the packet’s sender that the attempt failed.
• Allow the packet to enter (or leave) the private network.

105. Answers will vary. A callback modem verifies whether a user’s access is valid by logging the user off (after he or she attempts to connect to the network) and then calling the user back at a predetermined number. This method is useful in organizations with many employees who work off-site and who need to connect to the network from remote locations.

106. Answers will vary. Data encryption transforms data, called plaintext or cleartext, into a scrambled form called ciphertext that cannot be read by others. The rules for encryption, known as the encryption algorithm, determine how simple or complex the transformation process should be. The receiver then unscrambles the data by using a decryption key.
A commonly used encryption protocol is Secure Sockets Layer (SSL), which manages transmission security on the Internet. Next time you purchase an item online, notice that the http in the browser address bar changes to https. The https indicates a Secure HTTP connection over SSL. You might also see a padlock icon in the status bar at the bottom to indicate that your information has been encrypted and hackers cannot intercept it. A more recent cryptographic protocol is Transport Layer Security (TLS), which ensures data security and integrity over public networks, such as the Internet. Similar to SSL, TLS encrypts the network segment used for performing transactions. In addition to being encryption protocols, SSL and TLS have authentication functions.

107. Answers will vary. To increase the effectiveness of passwords, the following guidelines must be followed:
• Change passwords frequently.
• Passwords should be eight characters or longer.
• Passwords should be a combination of uppercase and lowercase letters, numbers, and special symbols, such as @ or $.
• Passwords should not be written down.
• Passwords should not be common names, such as the user’s first or last name, obvious dates (such as birthdays or anniversaries), or words that can be found in a dictionary.
• Passwords should not be increased or decreased sequentially or follow a pattern (for example, 222ABC, 224ABC, 226ABC).
• Before employees are terminated, make sure their passwords have been deleted.
• Do not use passwords that you have used before.

108. Answers will vary. Physical security measures primarily control access to computers and networks, and they include devices for securing computers and peripherals from theft. Proximity-release door openers are an effective way to control access to a computer room. A small radio transmitter is placed in authorized employees’ ID badges, and when they come within a predetermined distance of the computer room’s door, a radio signal sends a key number to the receiver, which unlocks the door.

109. Answers will vary. The Committee on National Security Systems proposed a model called the McCumber cube. John McCumber created this framework for evaluating information security. Represented as a three-dimensional cube, it defines nine characteristics of information security. The McCumber cube is more specific than the CIA triangle and helps designers of security systems consider many crucial issues for improving the effectiveness of security measures.