Protection Mechanisms in Operating Systems: A Comprehensive Guide for University Students

Question 1

Which memory protection technique allows different processes to share the same area of memory?

Accepted Answer

Segmentation and Paging

Answer

Segmentation

Answer

Paging

Answer

None of the mentioned

Question 2

In Unix-based systems, file permissions often involve which modes?

Accepted Answer

All of the mentioned

Answer

Read, Write, Execute

Answer

User, Group, Others

Answer

None of the mentioned

Question 3

Which authentication approach authenticates users by verifying their device?

Accepted Answer

Biometrics

Answer

Password

Answer

Two-factor authentication

Answer

Certificate-based authentication

Question 4

What is the primary function of a hardware memory management unit (MMU)?

Accepted Answer

To translate logical addresses into physical addresses

Answer

To allocate and release memory

Answer

To protect memory from unauthorized access

Answer

None of the mentioned

Question 5

Which protection mechanism separates processes and prevents unauthorized resource access?

Accepted Answer

Process isolation

Answer

Access control lists (ACLs)

Answer

Sandboxing

Answer

Encryption

Question 6

How do capabilities differ from access control lists (ACLs)?

Accepted Answer

Capabilities are given to processes, while ACLs are linked with objects.

Answer

ACLs are given to processes, while capabilities are linked with objects.

Answer

Capabilities and ACLs serve similar purposes.

Answer

None of the mentioned

Question 7

Which practice is considered optimal for implementing file permissions?

Accepted Answer

Granting users the minimum permissions necessary

Answer

Using default permissions whenever possible

Answer

Letting users change their own file permissions

Answer

None of the mentioned

Question 8

What is the purpose of a security kernel in an operating system?

Accepted Answer

To uphold the system's security policies

Answer

To provide a user-friendly interface for security settings management

Answer

To monitor the system for security breaches

Answer

None of the mentioned

Question 9

What is the main benefit of utilizing virtualization for security?

Accepted Answer

Isolation of virtual machines from each other

Answer

Reduced costs for hardware

Answer

Improved performance

Answer

None of the mentioned

Question 10

How does virtualization enhance system security? Explain the advantages of virtualization techniques over traditional operating systems in terms of security.

Accepted Answer

Virtualization provides secure sandboxing, isolating applications and preventing malicious software from spreading.

Answer

Virtualization improves system performance by optimizing resource allocation among multiple operating systems.

Answer

Virtualization reduces the need for physical hardware resources, making it more cost-efficient than traditional operating systems.

Question 11

Which memory protection technique divides memory into discrete and isolated segments, each with specific access permissions?

Accepted Answer

Segmentation

Answer

Paging

Answer

Time-sharing

Answer

Virtual memory

Question 12

What is the primary objective of file permissions?

Accepted Answer

To prevent unauthorized access and protect sensitive data

Answer

To streamline file organization and retrieval

Answer

To record file access patterns

Answer

To ensure data reliability

Question 13

Which of the following is NOT a typical user authentication method?

Accepted Answer

IP address

Answer

Password

Answer

Biometric scan

Answer

Token

Question 14

What is the main distinction between mandatory and discretionary access control?

Accepted Answer

Mandatory access control is centrally managed, while discretionary access control is user-managed

Answer

Mandatory access control is inherently more secure than discretionary access control

Answer

Discretionary access control is more flexible than mandatory access control

Answer

Mandatory access control is employed in trusted systems, while discretionary access control is used in untrusted systems

Question 15

Which of the following represents a potential vulnerability associated with memory protection?

Accepted Answer

Buffer overflow

Answer

Race condition

Answer

Deadlock

Answer

SQL injection

Question 16

What is the purpose of a reference monitor within an operating system?

Accepted Answer

To enforce access control rules

Answer

To allocate and manage virtual memory

Answer

To manage process scheduling

Answer

To handle system interrupts

Question 17

What is the core difference between symmetric and asymmetric cryptography?

Accepted Answer

Symmetric cryptography utilizes the same key for both encryption and decryption, while asymmetric cryptography employs distinct keys for each

Answer

Symmetric cryptography excels in speed compared to asymmetric cryptography

Answer

Asymmetric cryptography provides superior security over symmetric cryptography

Answer

Symmetric cryptography is used for digital signatures, whereas asymmetric cryptography is used for encryption

Question 18

Which of the following is NOT a key objective of protection mechanisms employed in operating systems?

Accepted Answer

Enhancing software functionality

Answer

Enforcing data integrity

Answer

Ensuring data confidentiality

Answer

Preventing unauthorized system access

Question 19

Which memory protection technique divides memory into variable-sized segments and assigns each process to a specific segment?

Accepted Answer

Segmentation

Answer

Paging

Answer

Virtual memory

Answer

Base-limit registers

Question 20

What type of file permission grants a user the ability to alter the contents of a file?

Accepted Answer

Write

Answer

Delete

Answer

Read

Answer

Execute

Question 21

Which user authentication method involves verifying a user's identity using a secret code or phrase?

Accepted Answer

Password-based authentication

Answer

Biometric authentication

Answer

Token-based authentication

Question 22

What is the primary purpose of a firewall in an operating system?

Accepted Answer

To monitor and control incoming and outgoing network traffic

Answer

To manage user accounts and permissions

Answer

To encrypt sensitive data

Answer

To detect and neutralize viruses and malware

Question 23

Which advantage is a key benefit of role-based access control?

Accepted Answer

Simplified user administration

Answer

Reduced hardware requirements

Answer

Enhanced data privacy

Answer

Improved system performance

Question 24

What is the main function of intrusion detection systems?

Accepted Answer

To identify and report potential security incidents

Answer

To enforce file access permissions

Answer

To recover lost or corrupted data

Answer

To prevent unauthorized system access

Question 25

Which vulnerability can potentially compromise the security of an operating system?

Accepted Answer

Buffer overflow

Answer

Role-based access control

Answer

Intrusion detection systems

Answer

Software updates

Question 26

Which protection mechanism is responsible for dividing system memory into separate sections, ensuring that processes are isolated from one another?

Accepted Answer

Memory protection

Answer

File permissions

Answer

Access Control Lists (ACLs)

Answer

User authentication

Question 27

Which authentication method requires users to provide something they have, such as a physical token or smart card?

Accepted Answer

Token-based authentication

Answer

Biometric authentication

Answer

Two-factor authentication

Answer

Knowledge-based authentication

Question 28

What security mechanism specifically prevents unauthorized changes to files or directories?

Accepted Answer

File permissions

Answer

System call interface

Answer

User authentication

Answer

Access control matrices

Question 29

Which protection mechanism safeguards memory areas from unauthorized access or modification?

Accepted Answer

Memory protection

Answer

File permissions

Answer

Virtualization

Answer

Encryption

Question 30

What is a potential drawback of Role-Based Access Control (RBAC)?

Accepted Answer

Managing a large number of user roles can be complex

Answer

High computational overhead

Answer

Lack of flexibility in assigning permissions

Answer

Vulnerability to privilege escalation

Question 31

Which benefit does virtualization provide in terms of protection?

Accepted Answer

Isolating untrusted software from the underlying system

Answer

Reducing memory overhead

Answer

Improving user experience

Answer

Increasing system performance

Question 32

What is the fundamental objective of protection mechanisms in operating systems?

Accepted Answer

To safeguard system resources from unauthorized access, modification, or destruction

Answer

To enhance system performance

Answer

To improve user convenience

Question 33

Which of the following is NOT a memory protection technique used in operating systems?

Accepted Answer

Multiplexing

Answer

Paging

Answer

Segmentation

Answer

Virtual memory

Question 34

Which protection mechanism ensures that each process has exclusive access to its allocated memory, safeguarding it from interference by other processes?

Accepted Answer

Memory Protection

Answer

User Authentication

Answer

Access Control

Answer

File Encryption

Question 35

What mechanism is primarily responsible for verifying the identity of users attempting to access system resources, preventing unauthorized access?

Accepted Answer

User Authentication

Answer

Process Isolation

Answer

File Permissions

Answer

Data Encryption

Question 36

What technique involves transforming data into an unreadable format to prevent unauthorized access and maintain data confidentiality?

Accepted Answer

Encryption

Answer

Salting

Answer

Obfuscation

Answer

Hashing

Question 37

Which of the following is a primary advantage of implementing robust protection mechanisms in an operating system?

Accepted Answer

Enhanced system security

Answer

Lower hardware requirements

Answer

Improved system performance

Answer

Reduced user workload

Question 38

What is the primary objective of process isolation?

Accepted Answer

To prevent a malfunctioning process from affecting other processes running on the system

Answer

To enhance user experience

Answer

To improve system performance

Question 39

What is the primary function of a firewall in the context of protection mechanisms?

Accepted Answer

To filter incoming and outgoing network traffic, blocking unauthorized access and malicious attempts

Answer

To encrypt data on the network

Answer

To detect and respond to cyberattacks

Answer

To authenticate users attempting to access the network

Question 40

What protection mechanism prevents a program from accessing memory outside its designated space, thereby safeguarding other processes and the operating system?

Accepted Answer

Memory Protection

Answer

File Permissions

Answer

Access Control Lists (ACLs)

Answer

User Authentication

Question 41

When a program running under a user account tries to access a file owned by another user, which protection mechanism primarily prevents this unauthorized access?

Accepted Answer

File Permissions

Answer

Memory Protection

Answer

User Authentication

Answer

Process Isolation

Question 42

Which of the following is NOT typically used for user authentication?

Accepted Answer

Physical Key

Answer

Biometrics

Answer

Password

Answer

Two-Factor Authentication

Question 43

What is the main purpose of the 'Segmentation' memory protection scheme?

Accepted Answer

Dividing a program's memory space into logical segments for controlled access

Answer

Preventing programs from accessing physical memory addresses

Answer

Protecting data from unauthorized access by other users

Question 44

Which statement accurately describes the 'Least Privilege' principle in operating system security?

Accepted Answer

A process should have only the minimum permissions necessary to execute its assigned tasks.

Answer

Users should be granted the highest privilege level for maximum efficiency.

Answer

The operating system should have unrestricted access to all system resources.

Question 45

What is the primary benefit of using a 'sandboxing' technique for software execution?

Accepted Answer

Isolating potentially harmful software from the main system to prevent damage.

Answer

Allowing multiple programs to safely share the same memory space.

Answer

Enhancing program performance by optimizing memory allocation.

Question 46

An operating system uses a technique where a user's permissions are associated with specific files and directories. What mechanism is this?

Accepted Answer

Access Control Lists (ACLs)

Answer

Memory Segmentation

Answer

User Authentication

Question 47

What is the primary purpose of a 'Security Kernel' within an operating system?

Accepted Answer

Enforcing security policies and protecting critical system resources.

Answer

Optimizing memory allocation for improved system performance.

Answer

Managing user accounts and authentication processes.

Question 48

A user logs into a system using both a password and a one-time code sent to their mobile device. What authentication scheme is this?

Accepted Answer

Two-Factor Authentication

Answer

Single Sign-On

Answer

Biometric Authentication

Answer

Password Authentication

Question 49

Which of the following is NOT a core component of a protection mechanism in an operating system?

Accepted Answer

Backup strategy

Answer

User authentication

Answer

File permissions

Answer

Memory protection

Question 50

Which memory protection technique divides the memory space into fixed-size blocks, each with its protection properties?

Accepted Answer

Segmentation

Answer

Paging

Answer

Encryption

Answer

Virtualization

Question 51

In a file system, which permission allows users to run an executable file?

Accepted Answer

Execute

Answer

Write

Answer

Read

Answer

Share

Question 52

Which authentication method verifies a user's identity based on what they know (e.g., password)?

Accepted Answer

Knowledge-based authentication

Answer

Token-based authentication

Answer

Biometric authentication

Question 53

What is the primary purpose of protection mechanisms in an operating system?

Accepted Answer

To prevent unauthorized access and modification of resources

Answer

To improve system performance

Answer

To simplify system management

Question 54

Which of the following access control mechanisms is mandatory?

Accepted Answer

Role-based access control

Answer

Access control list

Answer

Discretionary access control

Answer

Capability-based access control

Question 55

What is the main difference between discretionary and mandatory access control?

Accepted Answer

Discretionary access control is based on user-defined permissions, while mandatory access control is enforced by the system.

Answer

Discretionary access control is more secure than mandatory access control.

Question 56

Which protection mechanism uses sandboxing to isolate processes and limit resource access?

Accepted Answer

Virtualization

Answer

Encryption

Answer

Segmentation

Answer

Paging

Question 57

What is the primary advantage of using a capability-based access control system?

Accepted Answer

Ensures only authorized processes can access resources

Answer

Simplifies permission management

Answer

Improves system performance