An Intrusion Detection and Prevention System (IDPS) is a security solutions that monitor IT systems to detect and block suspicious behavior and known threats.
Given the escalating frequency and severity of cyberattacks, evidenced by over 60 billion records exposed to cyber breaches in recent years, a proactive security approach is essential. This is precisely where the value of an IDPS lies, acting as a layer of cyber protection.
To understand how an IDPS achieves this proactive protection, it’s important to recognize its core components. An IDPS incorporates an Intrusion Detection System (IDS), which passively monitors network traffic, identifies suspicious activity or known threats like malware, and generates alerts.
Building upon this detection capability is the Intrusion Prevention System (IPS). While an IDS only alerts, the IPS component actively works to block detected threats in real time. An IDPS integrates both detection and prevention functionalities into a unified security solution.
To help safeguard your business from cyber criminals, our essential guide explores IDPS’s workings, benefits, and best practices.
What Are the Types of IDPS?
Different types of Intrusion Detection and Prevention Systems are categorized by how and where they are deployed:
Network-Based IDPS
Network Intrusion Detection/Prevention Systems (NIDPS) monitor network traffic, actively detecting and preventing suspicious or malicious activity.
They are usually placed at strategic points within the network—behind firewalls, near routers, or at key traffic points.
Detection methods encompass:
- Signature-based: Matching traffic patterns against a database of known attack signatures.
- Anomaly-based: Identifying deviations from normal traffic flow.
- Protocol analysis: Monitoring how network protocols are used to detect misuse or irregularities.
Pros
- Can effectively spot network-level threats before they reach endpoints.
- Help provide a centralized overview of your traffic.
Cons
- Sometimes struggles with encrypted traffic.
- Can generate distracting and unhelpful false positives.
Host-Based IDPS
Host Intrusion Detection/Prevention Systems (HIDPS/HIPS) are installed directly on relevant devices (e.g. servers, workstations) to monitor activity.
Detection techniques include:
- File integrity monitoring: Flagging unauthorized changes to system files.
- Log analysis: Scanning system and application logs for signs of compromise.
- Registry monitoring (Windows): Detecting unauthorized registry changes.
- Behavioral monitoring: Checking for suspicious processes, scripts, or applications.
Pros
- Provides excellent insight into user behavior on devices.
- Highly effective at detecting insider threats and advanced malware.
Cons
- More admin-intensive and may not always be practical since it must be deployed and maintained on each workstation.
- Can consume system resources.
Wireless IDPS
Wireless Intrusion Detection/Prevention Systems (WIDPS/WIPS) secure wireless networks by detecting unauthorized access or anomalies over Wi-Fi.
They utilize dedicated sensors or are integrated into wireless access points and controllers.
Detection methods include:
- Rogue access point detection: Identifying unauthorized or spoofed Wi-Fi devices.
- Wireless protocol analysis: Detecting attacks targeting wireless standards.
- Signal analysis: Monitoring signal strength and patterns for anomalies.
Pros
- Offers protection against wireless-specific attacks and unauthorized access.
- Important in environments with guest Wi-Fi or BYOD (Bring Your Own Device).
Cons
- Can be difficult to manage in large, complex wireless environments.
- Susceptible to signal jamming.
Network Behavior Analysis (NBA)
Network Behavior Analysis (NBA) analyzes traffic patterns across the network to detect abnormal behavior that may indicate an attack.
NBA can operate as a standalone system or be integrated into broader IDPS or SIEM (Security Information and Event Management) platforms.
Detection techniques include:
- Traffic flow analysis: Spotting abnormal traffic volumes, such as DDoS activity or data exfiltration.
- Protocol analysis: Detecting irregular protocol usage or abuse.
- Statistical modeling: Using machine learning and statistical baselines to spot worrying anomalies and deviations.
Pros
- Effective at identifying zero-day attacks and advanced persistent threats (APTs).
- Complements traditional signature-based systems
Cons
- The system requires time to establish a baseline of “normal” behavior.
- False positives during baseline learning or network changes are common.
Hybrid Intrusion Detection and Prevention Systems
A hybrid setup combines features from multiple IDPS types to deliver layered protection.
It’s incorporated across endpoints, networks, and wireless infrastructure.
A hybrid IDPS may include:
- NIDPS to monitor for malicious traffic across the network
- HIDPS to check for anomalies on company devices
- NBA to detect complex or stealthy threats
Pros
- Provides comprehensive visibility and threat coverage.
- Reduces blind spots by analyzing and tracking data from multiple sources.
Cons
- More complex to configure and manage.
How Does IDPS Identify Threats?
An IDPS identifies cyber threats using the following strategies and techniques:
Signature-based detection
Signature-based detection relies on a database of known attack patterns or “signatures.” The IDPS then compares network traffic or device activity against these signatures.
A match, signaling a known attack, triggers an immediate alert.
This method is effective against known threats but is less precise against zero-day attacks or new variants of existing attacks.
Anomaly-based detection
Anomaly-based detection involves establishing a baseline of normal network or host behavior and then monitoring activity for deviations from this baseline.
Upon detecting a material deviation, the system generates an alert. Examples of deviations include:
- Unusual traffic
- Unauthorized access attempts
- Abnormal resource usage
This method can detect unknown or zero-day attacks but is known to produce false positives.
Protocol analysis
Protocol analysis focuses on spotting violations of network protocols and related irregularities.
The IDPS analyzes network traffic, checking that it complies with established protocols.
Any deviations from the standards, such as unusual data packets or unexpected protocol behavior, will trigger an alert.
Behavioral analysis
Behavioral analysis monitors the behavior of applications, users, and network devices for unusual activity. The IDPS establishes a baseline of normal behavior and then monitors for deviations.
For example, it might detect a user accessing sensitive files outside normal working hours or an application attempting to establish unauthorized network connections.
This method proves effective against insider threats and advanced persistent threats.
How Does IDPS Take Preventive Actions?
When an IDPS detects a threat, it typically takes one or more of the following actions
- Blocking malicious traffic: NIPS (Network Intrusion Prevention Systems) may automatically block malicious network traffic by dropping data packets or terminating connections.
- Terminating user sessions: The IDPS may terminate user sessions that are considered suspicious or outside the norm.
- Modifying firewall rules: The system can dynamically modify firewall rules to create a temporary barrier against breach attempts.
- Reconfiguring network devices: Tools reconfigure network devices, such as routers and switches, to isolate compromised systems or reroute traffic.
- Sending alerts and notifications: Alerts and notifications are sent to security teams to provide them with information about the flagged threat.
- Quarantine infected files or devices: HIPS (Host Intrusion Prevention Systems) can quarantine infected files or devices, preventing them from causing further harm.
- Rate limiting: The IDPS sometimes limits the rate of network traffic to prevent denial-of-service attacks.
- Preventing application exploits: The IDPS can prevent applications from being exploited by blocking malicious inputs or code.
What are the IPDS Best Practices?
For a dynamic and vigilant IDPS, follow these industry best practices:
Define clear objectives
Before implementing an IDPS, define and set clear policies that reflect your organization’s security goals. Whether you aim to detect unauthorized access, prevent specific attacks, or monitor compliance, this ensures the system aligns with your needs.
Optimize configuration
Customize the IDPS to your unique environment. Ensure that rules, policies, and detection triggers are tuned to differentiate between acceptable and unacceptable behaviors.
The goal is to reduce false positives and ensure the system responds swiftly to legitimate dangers.
Baseline normal activity
Establish a clear understanding of normal network and system behaviors. This helps the IDPS accurately identify anomalies and improves the chances of catching stealthy attacks.
Integrate IDPS with broader security technology
To build a multi-layered shield, combine the IDPS with other tools like firewalls and SIEM systems.
Use the advanced features of your IDPS (e.g. deep packet inspection, protocol analysis) to identify sophisticated attacks.
Monitoring and analysis
IDPSs generate a high volume of alerts, so it’s vital to have a system for analyzing and prioritizing these. The objective is to avoid alert fatigue while triggering prompt responses to genuine incidents.
Use a managed security service provider like Acrisure Cyber Services to ensure continuous professional vigilance.
Implement incident response procedures
Develop a comprehensive incident response plan detailing the steps when reacting to security incidents.
Automate alerts and ensure your security team is ready to act when threats are flagged.
Continuous review and testing
Regularly assess the performance of your IDPS. Review IDPS logs and reports to identify trends, patterns, and potential security weaknesses.
It’s also a good idea to simulate real-world attacks. These exercises sharpen your incident response procedures and test the readiness of your reaction team.
What Are the Benefits of an IDPS?
Let’s unpack the main benefits of an IDPS:
Early threat detection
IDPS aims to spot and stop malicious activity in real time. By blocking probes before they cause serious harm, your company avoids costly expenses such as:
- Infrastructure damage
- Reputational harm
- Lost data
- Business interruption.
- Regulatory penalties
With automated alerts and built-in response mechanisms, an IDPS allows your IT security team to react more quickly to threats.
Reduced data breach risk
Criminals are active 24/7, targeting customer records, financial information, and intellectual property, with 2024 recording 1.35 billion data breach victims alone. However, a strong IDPS reduces the risk of your critical data being compromised.
A responsible security image also helps build and maintain trust with clients and stakeholders.
Improved security visibility
An IDPS provides a detailed overview of your organization’s security landscape, presenting insights into your vulnerabilities and how they might be exploited.
This improved visibility helps detect threats outside the traditional network perimeter, mitigating risks associated with remote workforces and BYOD policies.
Compliance with regulations
IDPS solutions help organizations meet their regulatory compliance obligations. Detailed logging, alerting, and reporting capabilities make it easier to protect data as required by law.
This is especially crucial for sectors like healthcare, finance, and e-commerce, where regulations like HIPAA, PCI-DSS, and GDPR mandate proactive security controls.
How Can Acrisure Cyber Services Help With IDPS?
At Acrisure Cyber Services, our award-winning IT services have earned the trust of hundreds of clients of all sizes. Our cutting-edge managed security solutions, including Intrusion Detection and Prevention, offer essential peace of mind with around-the-clock protection.
With advanced threat detection and real-time response, our systems are tailored to meet your unique security environment. Every engagement starts with us thoroughly understanding that environment. By combining cutting-edge technology with ongoing support, we ensure your defenses evolve with the ever-changing threat landscape.
At Acrisure Cyber Services, your security is our priority, and our team is dedicated to 24/7/365 protection.
FAQs
How much do Intrusion Detection and Prevention services cost?
The costs of IDPS security solutions vary widely based on factors like:
- Business size
- Complexity
- System type
- Self-managed vs outsourced solution
Prices may range from under a thousand dollars to several thousand dollars per month, depending on the level of monitoring, support, and customization required.
Can small businesses benefit from IDPS solutions?
Small businesses can certainly benefit from this security setup. Cybercriminals are known to target smaller firms because of their weaker defenses. A properly scaled IDPS helps SMBs detect and respond to threats early, avoiding the cost and disruption of cyber breaches.
What are IDS rules?
IDS rules define the specific conditions or patterns that trigger alerts for suspicious network or device activity. These rules are crucial for identifying potential threats and cover:
- Known attack signatures
- Behavioral anomalies
- Policy violations
Regularly updating rules based on current threat intelligence and IT system changes ensures they remain current and effective.