intrusion prevention system (IPS)

An Intrusion Prevention System (IPS) is a security tool designed to detect and prevent threats within a network or system in real time. The IPS identifies potential intrusions and actively takes steps to stop or block malicious activities before they can cause harm. An essential part of Intrusion Prevention System is the network security technology that constantly monitors network traffic to identify threats. Under the general meaning of IPS, IPS technology is also an intrusion detection prevention system (IDPS).

What is an Intrusion Prevention System (IPS)?

An IPS is similar to an Intrusion Detection System (IDS), but it goes further by not only detecting suspicious activity but also taking automated actions to block or mitigate threats.

How IPS Works

An IPS monitors network traffic or activity within systems, constantly analyzing data to spot patterns and anomalies that may indicate potential threats, such as:

  1. Signatures of Known Threats: An IPS can use a signature-based approach, where it recognizes known attack patterns, like certain malware or exploit codes.
  2. Behavioral Anomalies: If the IPS detects unusual activity (e.g., an employee accessing confidential files outside of normal work hours), it may flag or block the action.
  3. Policy Violations: Some IPS systems look for activities that violate organizational policies, like unapproved applications attempting to run on the network.

How an IPS Supports Cybersecurity Goals

  1. Confidentiality:
    • By preventing unauthorized access, IPS helps protect sensitive information from external attacks (e.g., hackers) and internal misuse.
    • For example, if an IPS detects a brute-force attack on a database, it can block the attacker, keeping confidential data safe.
  2. Integrity:
    • IPS blocks potential attacks that may try to alter or corrupt data, such as injection attacks. This preserves data accuracy and trustworthiness.
    • If malware attempts to modify sensitive files, the IPS can intervene, preventing the data from being corrupted.
  3. Availability:
    • An IPS can prevent Distributed Denial of Service (DDoS) attacks, which aim to overwhelm and shut down network services. By doing so, it ensures that systems remain available to authorized users.
    • The IPS can detect high volumes of unusual traffic and block it, protecting the system from going offline due to overload.

Types of IPS

  1. Network-Based IPS (NIPS): Monitors the entire network for malicious activities. It’s usually installed at key points within the network to catch threats as data flows through.
  2. Host-Based IPS (HIPS): Monitors a single device, like a server or workstation, looking for suspicious activity or unauthorized changes within that system.
  3. Wireless IPS (WIPS): Focuses on securing wireless networks from threats specific to Wi-Fi, such as rogue access points.
  4. Network Behavior Analysis (NBA) IPS: Examines unusual patterns in network behavior, often useful in detecting insider threats and compromised devices.

Example Scenario

Imagine a company is targeted by a SQL injection attack on its customer database. A network-based IPS detects the malicious code pattern in an incoming query and blocks it in real-time, protecting the data from unauthorized access or tampering. This helps to prevent data breaches and maintains the integrity of customer data.

IPS and Modern Cybersecurity Practices

Today, many organizations use IPS as part of a Unified Threat Management (UTM) system, which combines IPS with other tools like firewalls, antivirus, and VPNs. This layered approach strengthens the security posture and provides a comprehensive defense against various attack vectors.