In today’s world, where digitalization is increasing at a massive speed, cyber threats or crimes are also increasing parallelly. To monitor the network traffic and system activities for suspicious behavior, enabling organizations to detect and respond to potential security breaches in real-time, systems like Intrusion Detection Systems play a huge role in protecting sensitive information or data. As cyber-attacks are becoming more problematic day by day, understanding the IDS’s functionality and its importance is very crucial in security measures.
Here, we have provided insights into the Intrusion Detection System and its components. Let’s dive into the pool of immense info on cybersecurity measures with IDS.
What is an Intrusion Detection System?
An Intrusion Detection System is a listen-only device and a network security technology that serves as a defense mechanism, and its key functions are monitoring network traffic, anomaly detection, alerting administrators, and detecting vulnerability exploits against a target application or computer. IDS is important to the security ecosystem. It operates as a defense for systems security when other technologies fail. It Identifies security incidents, analyzes the quantity and types of attacks, helps to identify bugs or problems with device configurations, supports regulatory compliance, and improves security responses.
Types of Intrusion Detection Systems

Network-based, Host-based, Protocol-based, Application protocol-based, and Hybrid are the five different types of IDS.
1. Network-based IDS
It is a completely protected network that is set up in important areas which are suspected more to be attacked. It analyzes the content of data and metadata that transfers to and from devices so that it can detect suspicious acts and timely alert administrators about the same.
2. Host-based IDS
A host-based IDS monitors the computer infrastructure and is deployed on specific endpoints to protect it against internal and external cyber threats. It also analyzes traffic and suspicious activities and notifies authorities.
3. Protocol-based IDS
These IDS are installed on a web server to monitor the behavior and state protocol and to analyze the protocol between a device and the server.
4. Application protocol-based IDS
The application protocol-based IDS are the systems that sit inside the server party and monitor and interpret application-specific protocols.
5. Hybrid IDS
The hybrid IDS combines two or more intrusion detection approaches, and by using this system, host agent data combines with the network information for a comprehensive view of the system. This system is considered as the most powerful one compared to others. Prelude is one such example of it.
How does an Intrusion Detection Systems Work?

Intrusion Detection Systems only needs to detect potential threats, and it is out of band on the network infrastructure. As a result, IDS is not in the real-time communication path between the sender and receiver of information. To analyze the copy of the inline traffic stream, it often takes advantage of a TAP or SNAP. This ensures that the IDS does not impact inline network performance.
The depth of analysis required to detect intrusion could not be performed quickly enough when it was developed. The speed would not keep pace with components on the direct communications path of the network infrastructure. The detection of suspicious activity to catch hackers with the help of network IDS is done, so that it can not damage the network.
There are IDSs. One is network-based, which is on the network itself, and the other is host-based, which is installed on client computers. An IDS works by looking for deviations from normal activity and known attack signatures. Anomalous patterns are sent up the stack and examined at the protocol and application layers. DNS poisonings, malformed information packets, and Christmas tree scans are the events that are detected by IDS, it can also be implemented as a network security device or a software application. It has also cloud-based IDSes so that it can protect data and systems in a cloud environment.
Intrusion Detection Systems Evasion Techniques Used by Invaders

There are so many techniques that are used by invaders to get protected from the detection of IDS. Sometimes, these techniques can create multiple challenges for the system to monitor them. Here, we will discuss some of these techniques. The first technique is Fragmentation, which divides it into smaller packets and allows invaders to remain sheltered, as there will be no attack signature to monitor. These fragmented packets are later rebuilt by the recipient node at the IP layer then they are forwarded to the application layer. These types of fragmented attacks are capable of generating malicious packets by replacing data in fragmented packets with newly formed data.
The second technique is Flooding, which invaders do by spoofing the legitimate UDP and ICMP. Intruders designed this technique to overwhelm the detector, triggering a failure of the control mechanism. When a detector fails, all traffic will then be allowed. It is used to camouflage the suspicious activities of the invader. As a result, IDS face difficulty in finding packets due to the excess volume of traffic.
The third one is Encryption, which offers several security capabilities such as data confidentiality, integrity, and privacy. Unfortunately, malicious software creators use security attributes to conceal attacks and evade detection, so that the attack on an encrypted protocol cannot be detected by any system. When the IDS cannot match encrypted traffic to existing database signatures, the encrypted traffic is not encrypted, which makes it very difficult for detectors to identify cyber-attacks.
The last technique is Obfuscation, which can be used to avoid being identified by making a message impossible to understand, thereby preserving an attack. It alters the program code in such a way that keeps it functionally non-differentiable. The objective is to reduce detectability to reverse engineering or static analysis processes by obscuring it and compromising readability. Obfuscating malware, for instance, allows it to evade IDSes.
Conclusion
Intrusion Detection Systems play a crucial role in the ongoing battle against cyber threats. As cyber crimes are rapidly increasing, taking advanced security measures is more important than ever. This system provides organizations with the ability to monitor suspicious activities, such as network traffic, and detect potential intrusions, allowing for timely responses to minimize risks. By the use of both network-based and host-based IDS systems, organizations can create a structured defense against negative cyber activities and will be able to ensure better protection of sensitive data and systems.
Moreover, as technology evolves, so too must the capabilities of IDS. The involvement of AI and machine learning in IDS increased their effectiveness, enabling them to identify new attack patterns and adapt to emerging cyber threats. It is clear that investing in robust intrusion detection not only safeguards individual organizations but also contributes to a more secure digital landscape for everyone.