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Key Network+ blog posts

Links to blog posts on the Network+ exam organized by topic similar to the Security+ blog link page.

Network+ N10-006 Practice Test Questions

Pass the Network+ Exam (N10-006) The First Time You Take It

At  $277, this exam is expensive.

Make sure you're ready before exam day!

Full bank of at least 293* realistic multiple choice practice test questions with in-depth explanations to help you pass the Network+ exam the first time you take it. This set also includes several performance-based questions.

 Network+ Study Materials

30 Day Package60 Day Package
Full bank of more than 293* N10-006 Network+ practice test questions.All questions include explanations so you'll know why the correct answers are correct, and why the incorrect answers are incorrect.CheckCheck
Performance-based QuestionsSeveral sets of performance-based questions. Question types include drag and drop, matching, and sorting type questions. See a demo here.checksmchecksm

Bonus #1

Flashcard Set
  • 200 Network+ Flashcards to reinforce key testable concepts
  • View in random and non-random modes.
checksm

Bonus #2

Subnetting mini-tutorial that will help you answer two key question types
  • Identify how many hosts a subnet supports
  • Identify valid IP addresses within a subnet
checksm

Get the Network+ Study Materials Here

All questions include explanations so you'll know why the correct answers are correct, and why the incorrect answers are incorrect. This way no matter how CompTIA words the questions, you'll be able to answer them correctly.Multiple quiz formats to let you use these questions based on the way you learn.
  • Learn mode. 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.
  • Test mode. In test mode, you can only see the correct answers and explanations after you complete the test.
This package allows you to go through the practice test questions in multiple ways based on how you learn best.
  • Domain 1 through 5** using Learn Mode
  • Domain 1 through 5 using Test Mode (Randomized)
  • The full bank of test questions using Learn Mode
  • The full bank of questions using Test Mode (Randomized)

Test your readiness with these quality questions

Understand the important important concepts using the explanations

 Network+ Study Materials

30 Day Package60 Day Package
Full bank of more than 293* N10-006 Network+ practice test questions.All questions include explanations so you'll know why the correct answers are correct, and why the incorrect answers are incorrect.CheckCheck
Performance-based QuestionsSeveral sets of performance-based questions. Question types include drag and drop, matching, and sorting type questions. See a demo here.checksmchecksm

Bonus #1

Flashcard Set
  • 200 Network+ Flashcards to reinforce key testable concepts
  • View in random and non-random modes.
checksm

Bonus #2

Subnetting mini-tutorial that will help you answer two key question types
  • Identify how many hosts a subnet supports
  • Identify valid IP addresses within a subnet
checksm

Get the Network+ Study Materials Here

Package includes several sets of performance-based questions.Two sets are simulated performance-based questions.Another set includes multiple performance-based questions using drag and drop capabilities. I love the way these new questions work. Check out a demo here.

You don't need to spend a fortune to get quality practice test questions

If you're like most people, you've already spent money on one or more Network+ books or courses. Now you need to ensure you understand the concepts and how they are tested. You can pay $100 or more for practice test questions, but you don't need to.

The set of practice test questions will give you a view of typical multiple choice questions you can expect to see on the live exam.

Get Certified Get Ahead with Network+ Practice Test Questions

 Network+ Study Materials

30 Day Package60 Day Package
Full bank of more than 293* N10-006 Network+ practice test questions.All questions include explanations so you'll know why the correct answers are correct, and why the incorrect answers are incorrect.CheckCheck
Performance-based QuestionsSeveral sets of performance-based questions. Question types include drag and drop, matching, and sorting type questions. See a demo here.checksmchecksm

Bonus #1

Flashcard Set
  • 200 Network+ Flashcards to reinforce key testable concepts
  • View in random and non-random modes.
checksm

Bonus #2

Subnetting mini-tutorial that will help you answer two key question types
  • Identify how many hosts a subnet supports
  • Identify valid IP addresses within a subnet
checksm

Get the Network+ Study Materials Here

Beware of questions that do not include explanations - many people have identified errors in these and even when there aren't errors, these types of questions encourage you to memorize answers instead of understanding the underlying concepts.* Don't you hate those little asterisks. Normally they mean "forget what you just read, it's not really true." Not so here though. The bank starts with 293 multiple choice practice test questions, but I'm still adding to them. There will be more.** CompTIA identified five domains of objectives for the CompTIA Network+ exam. They are:
  • 1.0 Networking Architecture
  • 2.0 Network Operations
  • 3.0 Network Security
  • 4.0 Troubleshooting
  • 5.0 Industry Standards, Practices, and Network Theory



Security+ Full Access Package

Get Certified Get Ahead Security+

Pass the First Time!

Up-to-date Content

New multiple-choice and performance-based questions added regularly

Pass the first time with quality practice test questions, performance-based questions, flashcards, and audio.

Buy The Full Access Study Package Today

60 Days Access For Only $65.97

Need more time? You can easily renew for another 60 days at a significantly reduced price.

All materials are available online shortly after making your payment.

Get the Security+ Full Access Study Package Here

Our online Security+ study materials are the perfect complement to the CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide. They can also be used to help ensure you're ready no matter what study guide you're using.

This exam is expensive.

Make sure you're ready before exam day. 

Here's what you'll get:
  • All of the multiple-choice questions from the best-selling CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide. See a demo here. All questions have full explanations so you'll know why the correct answers are correct and why the incorrect answers are incorrect.
  • Over 40 new multiple-choice questions we've added after publishing the study guide.
  • Over 30 performance-based questions. See a demo here.
  • All of the flashcards from the study guide. View them in any Web browser.
  • All of the audio from the study guide. Listen to a sample here.
  • Access to a free discount code for 10% off your Security+ voucher.

Buy The Full Access Study Package Today

60 Days Access For Only $65.97

All materials are available online shortly after making your payment.

Get the Security+ Full Access Study Package Here

Recent Posts

  • Symmetric Encryption Concepts

    Symmetric Encryption Concepts

    Symmetric encryption is a type of encryption that uses a single key to encrypt and decrypt data. If you’re planning to take the SY0-501 exam, you should have a basic understanding of cryptography concepts such as cipher types and cipher modes. …
  • Understanding Secure Coding Concepts

    Understanding Secure Coding Concepts

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  • Managing Accounts Principles

    Managing Accounts Principles

    When an account is active, access control methods are used to control what the user can do. Additionally, administrators use access controls to control when and where users can log on.  If you’re planning to take the SY0-501 version of the Security+ …
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    It’s common to implement several controls using a defense-in-depth strategy. If you’re planning to take the SY0-501 version of the Security+ exam, you should have a good understanding of frameworks, best practices, and secure configuration guides. This includes implementing defense-in-depth/layered security to protect …
  • Identifying Threat Actors

    Identifying Threat Actors

    When considering attacks, it’s important to realize that there are several different types of threat actors, and they each have different attributes. If you’re planning to take the SY0-501 version of the Security+ exam, you should have a basic understanding of threat actor …
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  • What’s in a Digital Certificate?

    What’s in a Digital Certificate?

    Digital certificates have a lot of data within them, and you should have a good understanding of what they contain, especially if you plan to take the SY0-501 version or the SY0-401 version of the Security+ exam. As an example, see if you can answer …
  • Security+ Multiple Choice Answers

    Security+ Multiple Choice Answers

    Apparently, the CompTIA SY0-501 Security+ exam is including as many as 6 or 8 multiple choice answers in multiple choice questions. Several readers have recently told me they were surprised to see so many questions requiring them to select multiple …
  • Identifying Baseline Deviations

    Identifying Baseline Deviations

    A baseline is a known starting point and organizations commonly use secure baselines to provide known starting points for systems.  If you’re planning to take the SY0-501 version or the SY0-401 version of the Security+ exam, you should have a basic understanding of baselines …
  • Comparing Personnel Management Policies

    Comparing Personnel Management Policies

    Companies frequently develop policies to specifically define and clarify issues related to personnel management. If you’re planning to take the  SY0-401 version or the SY0-501 version of the Security+ exam, you should have a basic understanding of common security policies. For example, can …
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    Can You Identify Common Malware Names

    Malware writers often use the same malware names to trick users. Educated cyber security professionals can usually identify these bogus malware names, but without some experience, it may be challenging. As an example, consider this sample Security+ practice test question …
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    Understanding Network Separation

    A common network security practice is to use different components to provide network separation. If you’re planning to take the SY0-501 or  SY0-401 Security+ exam, you should have a basic understanding of implementing secure network architecture concepts. This includes physical security and logical security methods …
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    Common Vulnerability Assessment Tools

    Vulnerabilities are weaknesses, and by reducing vulnerabilities, you can reduce risks.  If you’re planning to take the  SY0-401 version or the SY0-501 version of the Security+ exam, you should have a basic understanding of using appropriate vulnerability assessment tools that assess the security …

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

 

Symmetric Encryption Concepts

Posted by on August 13 in Security+ | 0 comments

Symmetric encryption is a type of encryption that uses a single key to encrypt and decrypt data. If you’re planning to take the SY0-501 exam, you should have a basic understanding of cryptography concepts such as cipher types and cipher modes.

For example, can you answer this practice test question?

Q. Which of the following is a symmetric encryption algorithm that encrypts data 1 bit at a time?

A. Block cipher

B. Stream cipher

C. AES

D. DES

E. MD5

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

Get Certified Get Ahead

Block Versus Stream Ciphers

Most symmetric algorithms use either a block cipher or a stream cipher. They are both symmetric, so they both use the same key to encrypt or decrypt data. However, they divide data in different ways.

A block cipher encrypts data in specific-sized blocks, such as 64-bit blocks or 128-bit blocks. The block cipher divides large files or messages into these blocks and then encrypts each individual block separately. A stream cipher encrypts data as a stream of bits or bytes rather than dividing it into blocks.

In general, stream ciphers are more efficient than block ciphers when the size of the data is unknown or sent in a continuous stream, such as when streaming audio and video over a network. Block ciphers are more efficient when the size of the data is known, such as when encrypting a file or a specific-sized database field.

An important principle when using a stream cipher is that encryption keys should never be reused. If a key is reused, it is easier to crack the encryption.

Remember this

Stream ciphers encrypt data a single bit, or a single byte, at a time in a stream. Block ciphers encrypt data in a specific-sized block such as 64-bit or 128-bit blocks. Stream ciphers are more efficient than block ciphers when encrypting data in a continuous stream.

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.

Cipher Modes

Block ciphers can use a variety of different modes of operation. It’s important to have a basic understanding of these modes when choosing cipher suites.

The Electronic Codebook (ECB) mode of operation is the simplest cipher mode mentioned in this blog. Algorithms that use ECB divide the plaintext into blocks and then encrypt each block using the same key. This represents a significant weakness. If any of the plaintext blocks are the same, the resulting ciphertext is the same, making it much easier to crack. ECB is not recommended for use in any cryptographic protocols today.

Cipher Block Chaining (CBC) mode is used by some symmetric block ciphers. It uses an IV for randomization when encrypting the first block. It then combines each subsequent block with the previous block using an XOR operation. Because encryption of each block is dependent on the encryption of all previous blocks, CBC sometimes suffers from pipeline delays, making it less efficient than some other modes.

Symmetric Encryption Algorithm

Counter (CTM) mode effectively converts a block cipher into a stream cipher. It combines an IV with a counter and uses the result to encrypt each plaintext block. Each block uses the same IV, but CTM combines it with the counter value, resulting in a different encryption key for each block. Multiprocessor systems can encrypt or decrypt multiple blocks at the same time, allowing the algorithm to be quicker on multiprocessor or multicore systems. CTM is widely used and respected as a secure mode of operation.

It’s worthwhile noting that the CompTIA objectives list CTM and include CTM in the acronym list as Counter-Mode. However, it’s much more common to see it listed as CTR or CM.

Galois/Counter Mode (GCM) is a mode of operation used by many block ciphers. It combines the Counter mode of operation with the Galois mode of authentication. Note that it doesn’t authenticate users or systems, but instead provides data authenticity (integrity) and confidentiality. In addition to encrypting the data for confidentiality, it includes hashing techniques for integrity. It is widely used due to its efficiency and performance, allowing systems to quickly encrypt and decrypt data.

Remember this

The Electronic Codebook (ECB) mode of operation is deprecated and should not be used. Cipher Block Chaining (CBC) mode combines each block with the previous block when encrypting data and sometimes suffers from pipeline delays. Counter (CTM) mode combines an IV with a counter to encrypt each block. Galois/Counter Mode (GCM) combines Counter mode with hashing techniques for integrity.


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. Which of the following is a symmetric encryption algorithm that encrypts data 1 bit at a time?

A. Block cipher

B. Stream cipher

C. AES

D. DES

E. MD5

Answer is B. A stream cipher encrypts data a single bit or a single byte at a time and is more efficient when the size of the data is unknown, such as streaming audio or video.

A block cipher encrypts data in specific-sized blocks, such as 64-bit blocks or 128-bit Advanced Encryption Standard (AES) and Data Encryption Standard (DES) are block ciphers.

Message Digest 5 (MD5) is a hashing algorithm.

See Chapter 10 of the CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide for more information on cryptography concepts.

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

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