Implementing Access Control Models

Posted by in Security+ | 0 comments

Do you know the various access control models? You should if you’re planning to take the Security+ exam. This post should help.

Here’s a sample practice test question:

Q. An organization has implemented an access control model that enforces permissions based on data labels assigned at different levels. What type of model is this?

A. DAC

B. MAC

C. Role-BAC

D. Rule-BAC

Can you answer the question? More, do you know why the correct answer is correct and the incorrect answers are incorrect? The answer and explanation is available at the end of this post.

Security+ Practice Test Questions

SY0-501 Practice Test Questions 

Over 300 realistic Security+ practice test questions

All questions include explanations so you'll know why the correct answers are correct,

and why the incorrect answers are incorrect.

Pass the Security+ Exam

the First Time You Take It

Multiple quiz formats to let you use these questions based on the way you learn.
  • Learn mode - randomized. View each of the questions in random order. Learn mode allows you to keep selecting answers until you select the correct answer. Once you select the correct answer, you'll see the explanation. Click here to see how learn mode works.
  • Learn mode - not randomized. View each of the questions in the same order. Use this if you want to make sure that you see all of the questions. Learn mode allows you to keep selecting answers until you select the correct answer. Once you select the correct answer, you'll see the explanation. Click here to see how learn mode works.
  • Test mode - randomized. View each of the questions in random order. In test mode, you can only see the correct answers and explanations after you complete the test. Click here to see how test mode works.
  • Test mode - not randomized. View each of the questions in the same order. In test mode, you can only see the correct answers and explanations after you complete the test. Click here to see how test mode works.
  • Test mode - 75 random questions. View 75 random questions from the full test bank similar to how the Security+ exam has a potential maximum of 75 multiple choice questions. In test mode, you can only see the correct answers and explanations after you complete the test. Click here to see how test mode works.

Get the full bank of SY0-501 Practice Test Questions Here

 SY0-501 Practice Test Questions


INCLUDES QUESTIONS TO HELP YOU PREPARE

FOR THE NEW PERFORMANCE BASED QUESTIONS 

Bonus - Performance Based Questions

Three sets of performance-based questions including over 30 questions. These questions show you what you can expect in the live exam. They include drag and drop, matching, sorting, and fill in the blank questions. See a demo here.

Bonus - Extra Practice Test Questions

New multiple-choice questions in the extra test bank. Questions are added occasionally. You can see what has been added recently here.

Get the full bank of Security+ (SYO-501) Practice Test Questions Here

Get the full bank of Security+ Practice Test Questions

Click here if you're looking for SY0-501 Full Study Package

Mandatory Access Control

The MAC model uses labels (sometimes referred to as sensitivity labels or security labels) to determine access. Security administrators assign labels to both subjects (users) and objects (files or folders). When the labels match, the system can grant a subject access to an object. When the labels don’t match, the access model blocks access.

Military units make wide use of this model to protect data. You may have seen movies where they show a folder with a big red and black cover page labeled “Top Secret.” The cover page identifies the sensitivity label for the data contained within the folder. Users with a Top Secret label (a Top Secret clearance) and a need to know can access the data within the Top Secret folder.

CompTIA Security+ Study Guide

The 501 Version of the Study Guide

The CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide is an update to the top-selling SY0-201, SY0-301, and SY0-401 study guides, which have helped thousands of readers pass the exam the first time they took it.  It includes the same elements readers raved about in the previous three versions.

Each of the eleven chapters presents topics in an easy to understand manner and includes real-world examples of security principles in action.

You’ll understand the important and relevant security topics for the Security+ exam, without being overloaded with unnecessary details. Additionally, each chapter includes a comprehensive review section to help you focus on what’s important.



Over 300 realistic practice test questions with in-depth explanations will help you test your comprehension and readiness for the exam. The book includes:

  • A 75 question pre-test
  • A 75 question post-test
  • Practice test questions at the end of every chapter.

Each practice test question includes a detailed explanation to help you understand the content and the reasoning behind the question. You’ll be ready to take and pass the exam the first time you take it.

If you plan to pursue any of the advanced security certifications, this guide will also help you lay a solid foundation of security knowledge. Learn this material, and you’ll be a step ahead for other exams. This SY0-501 study guide is for any IT or security professional interested in advancing in their field, and a must-read for anyone striving to master the basics of IT security.

Kindle edition also available.

Need to know is an important concept to understand. Just because individuals have a Top Secret clearance, it doesn’t mean they should automatically have access to all Top Secret data. Instead, access is restricted based on a need to know. Need to know is similar in concept to the principle of least privilege, but it only applies to data and data permissions. In contrast, the principle of least privilege applies to permissions and rights.

Security-enhanced Linux (SELinux) is one of the few operating systems using the mandatory access control model. SELinux was specifically created to demonstrate how mandatory access controls can be added to an operating system. In contrast, Windows operating systems use the discretionary access control model.

Implementing Access Control Models

Discretionary Access Control

In the DAC model, every object (such as files and folders) has an owner, and the owner establishes access for the objects. Many operating systems, such as Windows and most Unix-based systems, use the DAC model.

A common example of the DAC model is the NT File System (NTFS) used in Windows. NTFS provides security by allowing users and administrators to restrict access to files and folders with permissions. NTFS is based on the DAC model and the following section explains how it uses the DAC model.

SIDs and DACLs

Microsoft systems identify users with security identifiers (SIDs), though you will rarely see a SID. A SID is a long string of characters that is meaningless to most people and may look like this:

S-1-5-21-3991871189-223218. Instead of the system displaying the SID, it looks up the name associated with the SID and displays the name. Similarly, Microsoft systems identify groups with a SID.

Every object (such as a file or folder) includes a discretionary access control list (DACL) that identifies who can access it in a system using the DAC model. The DACL is a list of Access Control Entries (ACEs). Each ACE is composed of a SID and the permission(s) granted to the SID. As an example, a folder named Study Notes might have the following permissions assigned:

  • Lisa Full Control
  • Bart Read
  • Maggie Modify

Each of these entries is an ACE and combined they are a DACL.

The Owner Establishes Access

If users create a file, they are designated as the owner and have explicit control over the file. As the owner, users can modify the permissions on the object by adding user or group accounts to the DACL and assigning the desired permissions.

The DAC model is significantly more flexible than the MAC model described in the next section. MAC has predefined access privileges, and the administrator is required to make the changes. With DAC, if you want to grant another user access to a file you own, you simply make the change, and that user has access.

Remember this

The DAC model specifies that every object has an owner, and the owner has full, explicit control of the object. Microsoft NTFS uses the DAC model.


Full Security+ Course

SY0-501 Full Security+ Course

Helping you Pass the First Time

Online access includes all of the content from the

CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide

  • Introduction
  • About the exam (including information on the number of questions, test duration, passing score, types of questions and more. Also includes a listing of the exam objectives)
  • 75 question pre-assessment exam
  • Mastering Security Basics (full content from Chapter 1 of the study guide including the exam topic review and 15 practice test questions)
  • Understanding Identity and Access Management (full content from Chapter 2 of the study guide including the exam topic review and 15 practice test questions)
  • Exploring Network Technologies and Tools (full content from Chapter 3 of the study guide including the exam topic review and 15 practice test questions)
  • Securing Your Network (full content from Chapter 4 of the study guide including the exam topic review and 15 practice test questions)
  • Securing Hosts and Data (full content from Chapter 5 of the study guide including the exam topic review and 15 practice test questions)
  • Comparing Threats, Vulnerabilities, and Common Attacks (full content from Chapter 6 of the study guide including the exam topic review and 15 practice test questions)
  • Protecting Against Advanced Attacks (full content from Chapter 7 of the study guide including the exam topic review and 15 practice test questions)
  • Using Risk Management Tools (full content from Chapter 8 of the study guide including the exam topic review and 15 practice test questions)
  • Implementing Controls to Protect Assets (full content from Chapter 9 of the study guide including the exam topic review and 15 practice test questions)
  • Understanding Cryptography and PKI (full content from Chapter 10 of the study guide including the exam topic review and 15 practice test questions)
  • Implementing Policies to Mitigate Risks (full content from Chapter 11 of the study guide including the exam topic review and 15 practice test questions)
  • 75 question post-assessment exam
  • Glossary

Get the SY0-501 Full Security+ Course Here


Test your readiness with these quality materials

Random 75-question tests

Random practice tests from the all of the practice test questions in the CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide. All questions include explanations so you'll know why the correct answers are correct, and why the incorrect answers are incorrect.

3 sets Performance-based Questions

Three new sets of performance-based questions with a total of 30 questions. These new questions use a new testing engine that includes realistic drag and drop, matching, sorting, and fill in the blank questions.

Flashcard Set

  • 494 Online Security+ Glossary Flashcards
  • 222 Online Security+ Acronyms Flashcards
  • 223 Online Security+ Remember This Slide from the popular CompTIA Security+ Get Certified Get Ahead: SY0-501 Study Guide

Audio - SY0-501 Security+ Remember This Audio Files

Learn by Listening. Over one hour and 20 minutes of audio (MP3 downloads.)

Audio - SY0-501 Security+ Question and Answer Audio Files

Learn by Listening. Over two hours hour and 53 minutes of audio (MP3 downloads.)

Bonus #1

Audio from the end of chapter reviews from each of the chapters in the CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide. Over one hour and 40 minutes of additional audio.

Bonus #2

Access to all of the online content that is available for free to anyone that purchases the CompTIA Security+ Get Certified Get Ahead: SY0-501 Study Guide. This includes labs, extra practice test questions, and supplementary materials

Bonus #3 

Access the study materials for a total of 60 days because sometimes life happens.

Get the SY0-501 Full Security+ Course Here

Q. An organization has implemented an access control model that enforces permissions based on data labels assigned at different levels. What type of model is this?

A. DAC

B. MAC

C. Role-BAC

D. Rule-BAC

Answer is B. The mandatory access control (MAC) model uses labels assigned at different levels to restrict access.

The discretionary access control (DAC) model assigns permissions based on object ownership.

The role-based access control (role-BAC) model uses group-based privileges.

The rule-based access control (rule-BAC) model uses rules that trigger in response to events.

See Chapter 2 of the CompTIA Security+: Get Certified Get Ahead: SY0-401 Study Guide for more information on control types.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

CompTIA Security+ Get Certified Get Ahead: SY0-501 Study Guide

Subscribe To Our Newsletter

Join our mailing list and get a free excerpt of the CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide.  This excerpt includes the introduction and Chapter 1. 

You have Successfully Subscribed!

Get Certified Get Ahead is a participant in the Amazon Services LLC Associates Program,
an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com.

Copyright © 2015 Get Certified Get Ahead. All Rights Reserved.