Introduction
In today’s digital world, cyber threats are constantly evolving, making network security more important than ever. An “Intrusion Prevention System (IPS)” plays a crucial role in safeguarding networks by detecting and stopping malicious activities before they cause damage. It continuously monitors data traffic, identifies suspicious patterns, and automatically blocks potential attacks in real time. Whether it’s malware, exploits, or unauthorized access attempts, an IPS ensures that your system stays secure and resilient against modern cyber threats.
In this blog, we will help you understand what IPS in networking is, different threat detection as well as threat prevention methods in IPS, and its different types.
Before getting into more details, let us first understand what IPS in networking is.
What is IPS in Networking?
An intrusion prevention system (IPS) observes network traffic in real-time for potential threats and takes action on behalf of the security team to block those threats by alerting the security team, terminating risky connections, removing malicious content or sending signals to other security devices.
IPS in networking was developed from intrusion detection systems (IDSs), which detected and reported threats back to the security team. An IPS has the same threat detection and reporting functions as an IDS but also has automated threat prevention capabilities, making some IPSs also referred to as “intrusion detection and prevention systems (IDPS)”.
Since an IPS can block malicious traffic in real-time, it can help reduce the workload of security teams and security operation centers (SOCs) and help them focus on more complex and serious threats. Just as IPSs can block unauthorized actions taken by legitimate users, they can help enforce network security policies and help with compliance.
For example, an IPS can fulfill the Payment Card Industry Data Security Standard (PCI-DSS) requirements for intrusion detection measures.
IPS Threat Detection Methods
IPSs use three primary threat detection methods, exclusively or in combination, to analyze traffic. These are:
Signature-based detection
Signature-based detection techniques examine network packets for attack signatures, which are unique characteristics or behaviors associated with a specific threat. A signature could be a series of code that is observed in a specific variant of malware.
A signature-based IPS has a database of attack signatures that it will compare network packets against. If one of the signatures receives a match by a packet, the IPS will take action. Signature databases need to be updated regularly with new attack intelligence as new cyber-attacks emerge and known attacks evolve; nonetheless, signature-based IPSs can be bypassed by newly emerging attacks that have not yet been analyzed for attack signatures.
Anomaly-based detection
Anomaly-based detection techniques leverage artificial intelligence and machine learning to develop and iteratively enhance a baseline model of typical network activity. The IPS monitors network activity and compares it to the model, and it will take action any time it detects something that deviates from the model, such as a process using bandwidth more than what is typically considered normal, or a device opening a port that is generally closed.
Because anomaly-based IPSs act upon any identified abnormal behavior, they have the potential for detecting some unprecedented cyberattacks and blocking them even when they would have previously been missed by signature detection methods. They are also capable of detecting zero-day exploits – attacks that can utilize vulnerabilities in software before the software author is aware of the vulnerabilities and able to create a patch.
Policy-based detection
Detection methods based on policies follow the security policies defined by the security team. When a policy-based IPS detects an action that violates a security policy, it blocks the action.
For example, a SOC may create access control policies that define which users and devices are allowed to access a host. If an unauthorized user tries to access the host, a policy-based IPS would block them from doing so.
Policy-based IPSs definitely allow some customization and can be very useful, but they tend to have a lot of upfront costs. The security team needs to create a complete list of policies about what is allowed and what isn’t, anywhere in the network.
Less common threat detection methods
While most IPSs use the threat detection methods outlined above, some use less common techniques.
Reputation-based detection flags and blocks traffic from IP addresses and domains that are associated with malicious or suspicious activity. Stateful protocol analysis focuses on protocol behavior—for example, it might identify a distributed denial-of-service (DDoS) attack by detecting a single IP address making many simultaneous TCP connection requests in a short period.
IPS Threat Prevention Methods
When an IPS detects a threat, it logs the event and reports it to the SOC, often through a security information and event management (SIEM) tool (see “IPS and other security solutions”).
But the IPS doesn’t stop there. It automatically takes action against the threat by using techniques such as:
Blocking malicious traffic
An IPS may end a user’s session, block a specific IP address or even block all traffic to a target. Some IPSs can redirect traffic to a honeypot, a decoy asset that makes the hackers think they’ve succeeded when, really, the SOC is watching them.
Removing malicious content
An IPS may allow traffic to continue but scrub the dangerous parts, such as by dropping malicious packets from a stream or removing a malicious attachment from an email.
Triggering other security devices
An IPS may prompt other security devices to act, such as by updating firewall rules to block a threat or changing router settings to prevent hackers from reaching their targets.
Enforcing security policies
Some IPSs can prevent attackers and unauthorized users from doing anything that violates company security policies. For example, if a user tries to transfer sensitive information out of a database, it’s not supposed to leave; the IPS would block them.
Types of Intrusion Prevention Systems
IPS solutions can be software applications installed on endpoints, dedicated hardware devices connected to the network or delivered as cloud services. Because IPSs must be able to block malicious activity in real time, they’re always placed “inline” on the network, meaning traffic passes directly through the IPS before reaching its destination.
IPSs are categorized based on where they sit in a network and what kind of activity they monitor. Many organizations use multiple types of IPSs in their networks.
Network-based intrusion prevention systems (NIPS)
A network-based intrusion prevention system (NIPS) inspects traffic both to and from devices on the network. NIPS analyzes packets of data (often referred to as IP packets) for malicious activity. The NIPS monitors are placed throughout the network in a variety of locations. NIPS often will sit just behind the firewall at the network perimeter to stop incoming malicious traffic. NIPS can also be located in the network to monitor traffic arriving at and leaving from key assets, such as the one or more data centers or machines.
Host-based intrusion prevention systems (HIPS)
A host-based intrusion prevention system (HIPS) is implemented on a designated endpoint, such as a laptop or server, and monitors only traffic to and from that endpoint. HIPS are typically deployed alongside a network intrusion prevention system (NIPS) to provide an added layer of protection for critical assets. HIPS can also block malicious behavior from a node on the network that has been compromised, for example, a Ransomware attack spreading from an infected endpoint device.
Wireless intrusion prevention systems (WIPS)
A wireless intrusion prevention system (WIPS) is used to monitor wireless network protocols for signs of suspicious activity, such as unauthorized users and/or devices accessing a company’s wifi. If a WIPS identifies an unknown entity connected to a wireless network, it can sever the connection. A WIPS can also assist in identifying misconfigured or unsecured devices on a wifi network, in addition to intercepting man-in-the-middle attacks, when a hacker secretly monitors users communicating.
Network behavior analysis (NBA)
Solutions for network behavior analysis (NBA) observe network traffic flow. While NBAs can analyze packets like other IPSs, most NBAs focus on high-level aspects of the communication session, such as source and destination addresses, ports, and the number of packets sent.
NBAs use anomaly-based detection techniques, flagging and blocking any flows that differ from the standard normal, such as a DDoS attack on the traffic or a malware-infected device exfiltrating data to a command-and-control server.
IPS and other security solutions
While IPSs are available as standalone tools, they’re designed to be closely integrated with other security solutions as part of a holistic cybersecurity system.
IPS and SIEM (security information and event management)
IPS alerts are often funneled to an organization’s SIEM, where they can be merged with alerts and information from other security tools in a centrally managed console. This integration with SIEMs allows security teams to enhance IPS alerts with additional threat intelligence, filter out false positives and follow up on IPS activity to confirm that threats were successfully blocked. SIEMs also help SOCs correlate data from different types of IPSs since many organizations typically have more than one type of IPS.
IPS and IDS (intrusion detection system)
As mentioned earlier, IPSs evolved from IDSs and have many of the same features. While some organizations may use separate IPS and IDS solutions, most security teams deploy a single integrated solution that offers robust detection, logs, reporting and automatic threat prevention. Many IPSs enable security teams to shut off prevention functions, allowing them to act as pure IDSs if the organization desires.
IPS and firewalls
IPSs act as a second layer of protection in addition to firewalls. Malicious traffic is thwarted at the perimeter by firewalls, and IPSs stop anything that gets past the firewall and onto the network. Some firewalls, especially next-generation firewalls, have built-in IPS capabilities.
Frequently Asked Questions
Q1. What is IPS in Networking?
IPS in Networking is a security solution that observes the traffic on a network in real time, detects possible malicious threats, and automatically blocks those activities to protect data.
Q2. Is an IPS a Firewall?
No, an IPS is not a firewall. Firewalls filter traffic, whereas IPS actively analyzes and detects, then prevents malicious activities within network traffic.
Q3. Is IPS better than IDS?
Yes, IPS is better than IDS. IPS detects possible threats and also initiates preventive actions to stop the threats.
Q4. How does an IPS in Networking work?
IPS works by analyzing network traffic and identifying malicious patterns using detection methods, allowing the system to automatically block or isolate threats in real time.
Conclusion
An Intrusion Prevention System (IPS) is vital to protecting networks from cyber threats in real-time. IPS in Networking combines automated threat blocking, anomaly detection, and policy enforcement to improve an organization’s security posture and lessen the load on security teams. Whether it is hardware, software, or a cloud solution, IPS provides proactive protection from the evolving nature of attacks, allowing organizations to achieve compliance, protect sensitive information, and resist intrusion.
