Network-based Intrusion Detection System


A Network-based Intrusion Detection System (NIDS) is a security system designed to monitor network traffic. It identifies and alerts about suspicious activities or patterns that may indicate potential threats and vulnerabilities. The system operates by analyzing data packets flowing across a network to detect harmful activities such as cyber attacks or unauthorized access.


The phonetics for “Network-based Intrusion Detection System” is: Net-werk-beyst In-truh-zhun De-tek-shun Sis-tem

Key Takeaways

Three Main Takeaways about Network-based Intrusion Detection System

  1. Real-time Monitoring and Analysis: Network-based Intrusion Detection Systems (NIDS) facilitate real-time monitoring and analysis of traffic on the networks. They are proficient in analyzing incoming network traffic and identifying any potential threats that could harm the system.
  2. Proactive Threat Detection: These systems are proactive in their approach to identifying and mitigating threats. They analyze patterns and signature of data packets to detect any malicious activities or hacking attempts. Once a potential threat is detected, they can either send an alert or take more direct reactive measures.
  3. Comprehensive Coverage: As opposed to host-based systems, NIDS provide broader coverage as they monitor all network traffic. This means they have the ability to detect intrusions on any device connected to the network, making them a comprehensive solution for securing large, complex networks.


A Network-based Intrusion Detection System (NIDS) is crucial in today’s technology-dominated landscape because it offers a vital layer of security to protect against unauthorized, malicious activities. It constantly monitors and analyzes network traffic for suspicious activities and potential threats, such as malware, viruses, and hacker attacks. Operating at a strategic point or points within the network, the NIDS scrutinizes inbound and outbound traffic to detect any discrepancies in data flow that may indicate an intrusion or unauthorized access. With its real-time threat detection capability, it can provide timely alerts and facilitate quick response to avert potential damage or loss of data. Therefore, NIDS plays a critical role in safeguarding a network’s integrity and reliability, thus ensuring the smooth running of tech-driven operations.


A Network-based Intrusion Detection System (NIDS) serves a critical role in safeguarding the integrity, confidentiality, and availability of information within a network ecosystem. Its primary function is to identify and monitor any potentially harmful or unusual activity on a particular network in real-time. It does so by analyzing the traffic on the network to seek patterns or behaviors that might signal network security threats like hacking attempts, denials of service (DoS), port scans, or even worms and viruses. Depending on the configuration, upon detecting any suspicious activity, the NIDS can alert the system administrators or automatically initiate actions to halt the suspected invasion.Furthermore, the NIDS is used to maintain a reliable and secure network environment ensuring that organizational data, processes, and IT assets are safeguarded against cyber threats. It is generally deployed within the main network where it can examine incoming and outgoing traffic, become aware of various transactions occurring within the network, and dissect them to ascertain any malicious intents. Therefore, it’s like an ‘early warning system’ that can not only detect but also thwart cyber invasions before they can inflict significant damage, aiding in the proactive management of network security.


1. Snort: Snort is one of the most widely used network intrusion detection systems (NIDS) in the world. First established in 1998, it is an open-source system that is capable of real-time traffic analysis and packet logging. Snort functions by using a rule-based language combining with various detection methods to discover hostile malware and unauthorized activities.2. Cisco IOS Intrusion Prevention System (IPS): Operated by Cisco, one of the leading providers of networking solutions, this system offers comprehensive network security measures against threats. It is embedded into Cisco networking devices and might leverage global threat intelligence to identify threats, thus providing real-time, in-depth network intrusion detection.3. Suricata: This is an open-source network IDS, intrusion prevention system (IPS), and network security monitoring (NSM) solution. Developed by the Open Information Security Foundation, Suricata operates by inspecting network traffic using a powerful and extensive rules and signature language. It’s equipped with the ability to simultaneously capture, inspect, and correlate network traffic in real-time and offline modes.

Frequently Asked Questions(FAQ)

**Q: What is a Network-based Intrusion Detection System (NIDS)?**A: A Network-based Intrusion Detection System (NIDS) is a system used to monitor and analyze network traffic to protect it from unauthorized access or any harmful activities. It forms an essential part of network security by alerting administrators about potential attacks.**Q: How does NIDS work?**A: NIDS works by continuously monitoring the network traffic, identifying any suspicious patterns that may indicate a network or system attack from someone attempting to break into or compromise the system.**Q: What are the components of NIDS?**A: Key components of NIDS include sensors for data acquisition, analzyers to detect any suspicious activities, user interface for handling alerts, and a database for storing events and configurations.**Q: What is the difference between NIDS and Network-based Intrusion Prevention Systems (NIPS)?**A: While both systems are used to protect networks from intrusions, the key difference lies in their response to perceived threats. NIDS is a passive system used only to alert system administrators of potential threats, whereas NIPS is active and can take steps to prevent intrusions.**Q: Can NIDS prevent attacks?**A: No, NIDS cannot prevent attacks. It is designed to only detect potential intrusion attempts and alert system administrators.**Q: What are some examples of NIDS?**A: Some examples of NIDS include Snort, Suricata, Zeek (formerly known as Bro), and OSSEC.**Q: Are there any limitations of using NIDS?**A: Yes, like any system, NIDS have their own limitations. They can generate false positives, indicating an intrusion when there isn’t one. Also, they might fail to detect new, previously unseen attack patterns, leading to false negatives.**Q: What is the significance of NIDS in cybersecurity?**A: NIDS play a significant role in safeguarding a network’s security by monitoring traffic, detecting suspicious activities, and alerting the administrators to possible threats, thus allowing quick reactive measures.

Related Tech Terms

  • Anomaly detection: This term refers to the identification of unusual patterns or behaviors within a network that may indicate an intrusion or cyberattack.
  • Signature-based detection: This is a method used by network-based intrusion detection systems to identify attacks by looking for specific patterns, such as byte sequences in network traffic, or known malicious instruction sequences used by malware.
  • False positives: These are alerts generated by an intrusion detection system that incorrectly indicate a network intrusion. Managing and reducing false positives is a key challenge in network-based intrusion detection.
  • Packet sniffer: This is a program or device that can capture and analyze packets of information as they travel across a network. Packet sniffers are often a key component in network-based intrusion detection systems.
  • Firewall: While not a part of an intrusion detection system, a firewall is closely related as it is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

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