NEOCODE

Protection Domains & Security Threats MCQs

DOMAIN OF PROTECTION

1. What is a protection domain?

Correct Answer: a) A set of access rights for a process

Explanation:
A protection domain defines what system resources a process can access and what operations it can perform. Each user/process operates within a specific domain.

2. Which of the following is part of a protection domain?

Correct Answer: b) Access control list (ACL)

Explanation:
ACLs define which users/system processes can access specific resources and what operations they can perform, forming part of the protection domain.

3. How are protection domains enforced?

Correct Answer: a) By the operating system kernel

Explanation:
The OS kernel manages protection domains through mechanisms like memory management units (MMUs), system calls, and hardware-enforced privilege levels.

ACCESS MATRIX

4. What is an access matrix?

Correct Answer: a) A table defining permissions between subjects and objects

Explanation:
The access matrix model represents protection domains (rows) and objects (columns), with matrix entries specifying access rights (read, write, execute, etc.).

5. Which of the following represents a row in an access matrix?

Correct Answer: a) Domain

Explanation:
Each row represents a protection domain (subject), while columns represent objects, and cells contain the access rights that domain has for each object.

6. What is an Access Control List (ACL)?

Correct Answer: a) A column of the access matrix for an object

Explanation:
An ACL is associated with each object and lists which domains/users have what access rights to that object (vertical implementation of the matrix).

IMPLEMENTATION OF ACCESS MATRIX

7. Which data structure is commonly used to implement an access matrix?

Correct Answer: b) Access Control Lists (ACLs) and Capability Lists

Explanation:
ACLs (object-centric) and capability lists (subject-centric) are the two primary implementations of the abstract access matrix model.

8. What is a capability list?

Correct Answer: a) A row-wise implementation of the access matrix

Explanation:
A capability list is associated with each subject and contains tickets/capabilities representing their access rights to various objects.

9. Which is more efficient for large systems?

Correct Answer: b) Capability Lists

Explanation:
Capability lists scale better in large systems because checking permissions doesn't require searching through potentially large ACLs for each access.

SYSTEM AND NETWORK THREATS

10. Which is a common network threat?

Correct Answer: a) Denial-of-Service (DoS) attack

Explanation:
DoS attacks overwhelm systems with excessive requests (SYN floods, UDP floods) to make resources unavailable to legitimate users.

11. What is a Man-in-the-Middle (MitM) attack?

Correct Answer: a) An attacker intercepts communication between two parties

Explanation:
MitM attacks involve secretly relaying/altering communications between parties who believe they're directly communicating (e.g., via ARP spoofing or rogue access points).

12. Which attack floods a network with excessive traffic?

Correct Answer: b) DoS attack

Explanation:
DoS (Denial-of-Service) attacks overwhelm targets with traffic from single (DoS) or multiple (DDoS) sources, exhausting bandwidth or system resources.