Understanding IDSs and IPSs

Posted by in Security+ | 0 comments

If you’re planning to take the SY0-401 or the SY0-501 Security+ exam, you should have a basic understanding of how to analyze and interpret output from security technologies such as IDSs and IPSs.

For example, can you answer this question?

Q. A HIDS reported a vulnerability on a system based on a known attack. After researching the alert from the HIDS, you identify the recommended solution and begin applying it. What type of HIDS is in use?

A. Network-based

B. Signature-based

C. Heuristic-based

D. Anomaly-based

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.

Comparing IDSs and IPSs

Intrusion detection systems (IDSs) monitor a network and send alerts when they detect suspicious events on a system or network. Intrusion prevention systems (IPSs) react to attacks in progress and prevent them from reaching systems and networks.

As an introduction, administrators use protocol analyzers, or sniffers to capture and analyze network traffic sent between hosts. IDSs and IPSs have the same capability. They capture the traffic and analyze it to detect potential attacks or anomalies.

Both IDSs and IPSs have the ability of detecting attacks using similar detection methods. The biggest difference is in their responses to an attack. It’s worth remembering that IDSs and IPSs can implement the same monitoring and detection methods.

HIDS

A host-based intrusion detection system (HIDS) is additional software installed on a system such as a workstation or server. It provides protection to the individual host and can detect potential attacks and protect critical operating system files. The primary goal of any IDS is to monitor traffic. For a HIDS, this traffic passes through the network interface card (NIC).

Many host-based IDSs have expanded to monitor application activity on the system. As one example, you can install a HIDS on different Internet-facing servers, such as web servers, mail servers, and database servers. In addition to monitoring the network traffic reaching the servers, the HIDS can also monitor the server applications.

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.

It’s worth stressing that a HIDS can help detect malicious software (malware) that traditional antivirus software might miss. Because of this, many organizations install a HIDS on every workstation as an extra layer of protection in addition to traditional antivirus software. Just as the HIDS on a server is used primarily to monitor network traffic, a workstation HIDS is primarily used to monitor network traffic reaching the workstation. However, a HIDS can also monitor some applications and can protect local resources such as operating system files.

In other organizations, administrators only install a HIDS when there’s a perceived need. For example, if an administrator is concerned that a specific server with proprietary data is at increased risk of an attack, the administrator might choose to install a HIDS on this system as an extra layer of protection.

NIDS

A network-based intrusion detection system (NIDS) monitors activity on the network. An administrator installs NIDS sensors or collectors on network devices such as routers and firewalls. These sensors gather information and report to a central monitoring server hosting a NIDS console.

A NIDS is not able to detect anomalies on individual systems or workstations unless the anomaly causes a significant difference in network traffic. Additionally, a NIDS is unable to decrypt encrypted traffic. In other words, it can only monitor and assess threats on the network from traffic sent in plaintext or nonencrypted traffic.

Understanding IDSs and IPSs

NIDS sensors

The figure shows an example of a NIDS configuration. In the figure, sensors are located before the firewall, after the firewall, and on routers. These sensors collect and monitor network traffic on subnets within the network and report to the NIDS console. The NIDS provides overall monitoring and analysis and can detect attacks on the network.

NIDS sensors

The figure also shows a tap or port mirror on the internal switch. Most switches support port mirroring, allowing administrators to configure the switch to send all traffic received by the switch to a single port. After configuring a port mirror, you can use it as a tap to send all switch data to a sensor or collector, and forward this to a NIDS. Similarly, it’s possible to configure taps on routers to capture all traffic sent through the switch and send it to the IDS.

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

Detection Methods

An IDS can only detect an attack. It cannot prevent attacks. In contrast, an IPS prevents attacks by detecting them and stopping them before they reach the target. An attack is any attempt to compromise confidentiality, integrity, or availability.

The two primary methods of detection are signature-based and heuristic- or behavioral- based (also called anomaly-based). Any type of IDS can detect attacks based on signatures, anomalies, or both. The HIDS monitors the network traffic reaching its NIC and the NIDS monitors the traffic on the network.


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

Q. A HIDS reported a vulnerability on a system based on a known attack. After researching the alert from the HIDS, you identify the recommended solution and begin applying it. What type of HIDS is in use?

A. Network-based

B. Signature-based

C. Heuristic-based

D. Anomaly-based

Answer is B. If the host-based intrusion detection system (HIDS) identified a known issue, it is using signature-based detection.

A HIDS is not network-based.

Heuristic-based or anomaly- based (sometimes called behavioral-based) detection systems identify issues by comparing current activity against a baseline. They can identify issues that are not previously known.

See Chapter 4 of the CompTIA Security+: Get Certified Get Ahead: SY0-501 Study Guide

or

Chapter 4 of the CompTIA Security+: Get Certified Get Ahead: SY0-401 Study Guide

for more information on securing a network.

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.