Network based Intrusion Detection System (NIDS) is an important layer of security in the cybersecurity world. It essentially acts as a proactive guard, constantly scrutinizing network traffic activity — watching the data packets that travel across your devices for patterns that suggest signs of unauthorized access and other malicious behavior.
By bringing the highest level of network defense strategies and a full understanding of what an NID system is capable of, you have a greater chance of keeping your organizational data safe from this ongoing threat in cyberspace. But first, let’s start with understanding – what is Network Intrusion Detection Systems?
What is a Network based Intrusion Detection System?
Network based intrusion detection system, or NIDS for short, is a fundamental security program used to monitor your network traffic to check if anything looks suspicious. It’s a virtual lookout that is constantly screening the traffic flow, trying to spot anything that is inherently suspicious. Essentially an NIDS does what a firewall does, but instead of just blocking the known threats, it goes a step further by actively spotting patterns or anomalies to detect network intrusion.
NIDS can be in one of two forms: it could either be inline or passive. An inline NIDS is located right in the network path: it monitors every single bit of traffic that passes through it. Passive NIDS on the other hand is placed at a tap for SPAN port where it gets a replica of the traffic that is being analyzed without blocking any of the actual traffic flow. Overall, passive notifications have all the advantages of an inline, but it doesn’t intervene in the data process which means that the operation doesn’t affect the actual traffic flow.
Step-by-Step Process for Setting Up NIDS
Network based intrusion detection entails monitoring and analyzing network traffic to detect network intrusion or security threats. Here’s a step-by-step guide to effectively set up network based intrusion detection:
1. Choose the Right NIDS Solution
NIDS software or hardware solution should be chosen by keeping the size of the network and the level of security in mind. However, consider that traditional NIDS solutions have evolved into Network Detection and Response (NDR) systems, which not only detect threats but also provide automated responses and deeper visibility into network activity, making them a more robust choice for modern security challenges.
2. Identify Critical Network Points
Place NIDS sensors at strategic network points such as perimeter defenses, internal network segments, and high-traffic areas like servers and databases. Sensors should be placed in choke points where many of the network services traverse.
3. Baseline Network Traffic
Monitor the network over time to baseline a pattern so the tool can distinguish between normal behavior and malicious activities.
4. Configure NIDS Rules
Define rules or signatures to detect network intrusion attack types such as:
- Malware and Virus Signatures
- Unusual Protocol Use
- Port Scans
- Denial of Service (DoS) Attacks
- Unauthorized Access Attempts
Ensure rules are updated regularly, either manually or through an automatic update service, to detect emerging threats.
5. Monitor Network Traffic in Real-Time
Continuously monitor traffic and alerts in real-time. NIDS solutions generally capture and analyze data packets using methods such as deep packet inspection (DPI) to detect malicious patterns in the payload.
6. Analyze Suspicious Activity
When an alert is generated, investigate suspicious activities by analyzing the source and destination IP addresses, time of access, ports used, and the type of traffic. Look for patterns like:
- Large amounts of data are being transferred to unfamiliar external IPs (potential exfiltration).
- Repeated login failures (brute-force attack).
- Traffic to or from unexpected countries or regions.
7. Correlate with Other Systems
Assist the NIDS alerts with other logs from other security tools like host-based IDS, antivirus firewall, and others.
8. Respond to Intrusions
Develop an incident response plan that dictates how to respond to various alerts. Take actions like:
- Blocking malicious IPs.
- Quarantining affected systems.
- Initiating a full forensic investigation to assess the damage and scope of the attack.
9. Regularly Update NIDS
NIDS systems should be updated on a regular basis to detect new threats. This includes constantly updating network intrusion detection signatures, intrusion rules, and the software as soon as new versions are released. However, modern Network Detection and Response (NDR) solutions offer an edge by using AI-driven analytics and behavioral monitoring, reducing reliance on manual updates while improving detection of emerging and sophisticated threats.
10. Review and Optimize
Regularly review the NIDS logs to trim the system. Distinguish false positives and reduce nuisance hits by editing the rules.
Network based intrusion detection is an ongoing process that requires vigilant monitoring, regular updates, and quick response to threats. By integrating it into a broader cybersecurity strategy, organizations can greatly enhance their defense against network-based attacks.
Common Challenges in Implementing NIDS Solutions
Although Network Intrusion Detection Systems are vital for protecting network infrastructure, they seem to bring a range of challenges in terms of implementation. To ensure that the technology is implemented effectively, it is important to understand and address the issues that may arise. Here are some of the most frequent problems associated with the implementation of NIDS:
1. False Positives and False Negatives
One of the most frequent problems associated with NIDS is determining how to avoid false alarms that may pose a serious threat to security specialists’ work. Designing optimal detection algorithms is a hard task, as stringent mechanisms may start providing too many false alarms while more lenient settings may not be able to recognize true threats as such.
2. High Network Traffic
High-traffic systems provide NIDS with a lot of information that needs to be inspected. Therefore, the system may become overwhelmed, and the performance may plateau, which may be harmful and dangerous in terms of detecting and responding to ICD-related threats.
3. Encrypted Traffic
More and more organizations have started employing traffic encryption as a way to avoid data theft. It seems to be very helpful for digital security, but it creates blind spots for NIDS, as they are not able to detect or predict threats if they are encrypted.
4. Evolving Threats
Cyber-attacks are continuously evolving, while threat actors develop new strategies and solutions for bypassing conventional or other types of NIDS. Thus, safety specialists are required to constantly update their detection rules and algorithms, which may be costly and time-consuming.
5. Integration with Other Security Tools
NIDS solutions often need to work in tandem with other security systems, such as firewalls, SIEMs, and endpoint detection tools. Ensuring seamless integration and communication between these systems can be complex, potentially creating silos of information that hinder overall network visibility.
How Fidelis Network® Tackles These Challenges
The Fidelis Network Detection and Response solution is designed to address many of the concerns and difficulties typically associated with traditional NIDS. By leveraging advanced machine learning and behavioral analytics, Fidelis Network® reduces false positives and false negatives so the security team can focus on genuine threats.
Moreover, Fidelis employs efficient traffic inspection mechanisms that can be used to penetrate and process data in large quantities without performance loss. And it fully supports deep packet inspection, eliminating the blind spot of encrypted traffic.
Fidelis Network® is also extremely scalable, whether in a small or large environment. Furthermore, the platform continuously updates its threat intelligence and detection algorithms to stay ahead of evolving cyber threats.
Lastly, for better integration, you can choose Fidelis Elevate®, an Extended Detection and Response (XDR) solution as it ensures a unified approach to network security, to further enhance the capabilities of Fidelis NDR Solution across endpoints, networks, and cloud environments.
