IDS System: A Complete Brief For Beginners
Tags: cybersecurity, security, writing, beginners
Published: 2023-02-26 10:34:08

When it comes to securing an IT infrastructure, a lot of high-end mechanism and systems comes into action. And one of the systems is IDS. Nowadays, it has a become a must for every organization, if they want to prevent attackers from performing unauthorized activities. 

And if you are someone who works in the cyber-security industry, a security enthusiast or someone who wants to work in the security domain. Then, it’s really important to clear the IDS fundamentals.
 
So, let’s get started to understand IDS basics within 5 minutes.

## What does IDS Stands For? 
In cyber-security, IDS is a crucial security mechanism abbreviated for Intrusion Detection System. As the name suggests, IDS get used for detecting the malicious activities being performed on a computer or on an entire network. 

An IDS system monitors the system or network and alerts the authorized persons, if it detects anything abnormal. Then, the security experts investigate about the alert and takes further action accordingly. Primarily IDS system is of two types, namely: 

**#1: Host-Based Intrusion Detection System (HIDS)**

The HIDS gets configured on endpoint systems, such as your personal system or an employee’s computer system in an organizational network. Such type of IDS dedicatedly monitors the ongoing and incoming of traffic on that particular device. And provides only a limited visibility. 

If something abnormal/malicious happens on the system, it alerts the administrator; otherwise, it doesn’t. 

**#2: Network-Based Intrusion Detection System (NIDS)** 

The NIDS system covers the entire organizational network. It monitors the overall incoming an outgoing traffic in a network to detect each malicious activity. Primarily, NIDS analyzes the metadata of data packets getting transferred over a network. In addition, with its implementation, visibility across network increases and security experts avails a wider view in preventing cyber-attacks.

However, the only drawback is that it doesn’t provide deep insight of endpoint systems.

## Detection Methods Used By Intrusion Detection System 

IDS systems used three different methods to finalize, whether an activity is malicious or not. And the methods include: 

**#1: Signature-Based Detection Method**

In this method, a signature gets created of all the pre-discovered malware and cyber-attacks. Then the list is takes as primary reference by the IDS system. When the IDS discover similar signature on the system or in network, it sends an alert. 

**#2: Anomaly-Based Detection Method**
 
Anomaly-based refers to behavior-based IDS. This type of detection approach works on the principle of discovering abnormal behaviors. A model of normal behavior gets build and the system constantly cross-verifies the current activity to it. If any activity or operations mismatches with it, alert gets triggered. 

**#3: Policy-Based Detection Method**

A policy-based IDS system works in the custom standards and protocols configured by an organization. It cross-verifies the activity with the policy list and trigger alerts accordingly. 

For instance, if you set a policy that no employee can login to the network after working hours. But, someone tries to login after the defined hours. Then, IDS will send an alert to security team. 

## Types of Alerts Associated With an IDS System 
An Intrusion Detects System provides four types of alerts and an administrator has to understand them to take appropriate action:
 
**#1: True Positive Alert:** Malicious activity gets identified as potential threat/cyber-attack. 

**#2: True Negative Alert:** Legitimate activity is identified as legitimate traffic. 

**#3: False Positive Alert:** Legitimate activity gets identified as an attack. 

**#4: False Negative Alert:** Malicious activity gets identified as legitimate activity.  

## Bonus Tip To Solidify Security 
Whenever you configure an IDS system, follows the below aspects: 
* Configure a log server with IDS to store entries. 
* Frequently scan the logs, as it will help to detect activities missed by IDS system. 
* In addition, logs will also aid in finding the root cause of an attack. But always remember to scan the files offline for better results. 

## Final Thoughts 
IDS is must for maintaining the digital security, as it helps to effortlessly detect malicious activities. You must utilize the HIDS and NIDS in collaboration to get better and deep visibility of the entire network. It will help you prevent attackers, aiming to exploit a specific system or the network. In addition, you must utilize all three detection methods to get better results and to maintain data integrity, confidentiality and availability.