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What is the Intrusion Prevention System (IPS)?

One of the most important cornerstones of network security is the intrusion prevention system. An intrusion prevention system (IPS) is a technology that detects malicious activities on a network or system. An intrusion prevention system (IPS) combines an intrusion detection system with a response or control system. Intrusion prevention systems work by detecting harmful behavior, capturing and reporting information about the malicious activity, and attempting to prevent it before happening.

IPS solutions are now available in three forms:

  1. Specific hardware and software (either physical or virtual appliances)
  2. IPS capabilities embedded in existing business network security protocols
  3. Cloud-based IPS services.

The most effective strategy to avoid intrusion is to never use vulnerable software. Unfortunately, this aim is unachievable due to the hundreds of new vulnerabilities reported every day in various software, but their considerably more effective equivalents in the realm of intrusion prevention have not seen nearly as extensive implementation. Intrusion detection systems (IDS) are extremely valuable as an essential component of a security administrator's toolkit, but their considerably more powerful equivalents in the field of intrusion prevention have not seen nearly as broad adoption.

If there is one constant in the world of intrusion detection and by extension, intrusion prevention, it is the requirement for continuous tweaking, evaluating, and monitoring to maintain appropriate operation. There may be a significant time delay between the announcement of a software vulnerability and the release of a patch to fix the problem. Meanwhile, how can security be maintained? An intrusion prevention system (IPS) enables detailed judgments about the sorts of interactions permitted on a host or network, and in the case of insecure software that must stay available, it may be the only way to improve security.

What are Intrusion Prevention System Features?

Here are the main features of the IPS:

  • The IPS has a selective logging feature that captures network activity only when it takes action, protecting network users' privacy.
  • The IPS protects privacy by comparing network traffic to a list of known harmful traffic and without storing or viewing content.
  • In IPS-connected systems, there are fewer security issues. While linked units may not notice any changes, the IPS guarantees that complete systems are less disrupted and that security incidents are minimized.
  • The IPS defends against a variety of threats. It protects against zero-day risks, minimizes brute-force password attempts, and protects against availability threats like DDoS attacks.
  • The IPS can block efforts to identify open ports on specific hosts or attacks on the SSL protocol.

Why are Intrusion Prevention Systems Important?

As corporations expand to dispersed platforms, the security landscape becomes more complex, and intruders are increasingly targeting network computers. In this situation, the need for an intrusion prevention system in defending endpoint devices and business networks against sophisticated threats becomes more critical than ever.

To ensure secure and reliable sharing of information across diverse businesses, modern networked business settings necessitate a high level of security. An intrusion prevention system, unlike older technologies, serves as an adjustable safeguard strategy for system security. The capacity to prevent intrusions by an automated reaction rather than requiring IT intervention results in lower costs and more performance flexibility.

The capacity of network intrusion prevention systems to identify and block a range of threats that cannot be detected automatically by firewalls, antivirus technologies, and other corporate security measures is the most important feature it provides compared to other systems.

In many cases, IT or security administrators can find it difficult to quickly review alerts and take action. If too many security breaches are detected and reported at the same time by the intrusion detection system, they may not be able to respond to all of them. In this case, IPS can intervene quickly based on the predetermined security protocol and protect the system against threats.

How Do Intrusion Prevention Systems Work?

Intrusion prevention systems operate by monitoring network traffic as it flows across the network; unlike an intrusion detection system, which is only designed to respond, an intrusion prevention system is designed to prevent malicious events from occurring by blocking attempts as they occur. An IPS can block a variety of attacks, including denial of service (DOS), distributed denial of service (DDOS), exploits, worms, and viruses.

IPS infrastructure analyzes the network flow in real-time and compares the data in the stream with the attack patterns that are pre-registered in its database. If a packet is confirmed to be malicious, an IPS may discard it and then block all future communication from the attacker's IP address or port. Legitimate traffic can continue to flow without causing any perceived service interruptions.

Different detection mechanisms are used in intrusion prevention systems. These are:

  • Address matching
  • General pattern matching
  • Packet anomaly detection
  • HTTP string and substring matching
  • TCP connection analysis
  • Traffic anomaly detection
  • TCP/UDP port matching

Typically, IPSs capture information about observed events, alert system administrators, and generate reports. To aid in network security, an intrusion prevention system (IPS) can automatically receive preventive and security updates to continually monitor and stop developing Internet threats.

In addition to all of these detection capabilities, several IPS solutions provide the detection and prevention of additional forms of threats. For example, an intrusion prevention system (IPS) may provide a function comparable to application whitelisting that controls which executables may be launched. Similarly, against a possible threat, IPS stores the intelligence information it receives about its previous behavior and can restrict IP addresses, web addresses, and certain organizations. Some network intrusion prevention systems can also do extensive, sophisticated analysis of files sent over network connections to detect anomalous activity associated with utilizing or running these files.

Many intrusion prevention systems (IPS) can also respond to an identified threat by actively blocking it from succeeding. They employ a variety of response approaches. Here are the approaches listed below:

  • Notifying system administrators of potential security breaches by sending automated alarms.
  • Discarding detected malicious packets.
  • Blocking traffic from the malicious IP address and resetting the connection.
  • Setting up a firewall to improve security against previously identified vulnerabilities
  • Removing otherwise dangerous sections of an email, such as misleading links, and replacing them with warnings regarding the removed material

Four types of IDS and IPS situations are as follows:

  1. True positive
  2. True negative
  3. False-positive
  4. False-negative

Implementing an IDS or IPS should result in only genuine positives and true negatives.

It is important to remember that most solutions contain false positives, which cause monitoring engineers to spend time analyzing non-malicious events, as well as false negatives, which can lead to intrusions. As a result, correct system setup is critical since it must mirror the organization's traffic patterns.

What is Intrusion Prevention System Techniques?

Intrusion Prevention Systems detect intrusions using one of the following three techniques:

1. Anomaly-based

An anomaly-based intrusion prevention system (IPS) analyzes the network traffic and randomly selects network traffic samples and compares them to a pre-calculated baseline performance level. When the received network traffic sample shows a mismatch within the predetermined parameters, the IPS steps in to resolve the situation.

This baseline is used to determine what is "typical" in a network, such as the amount of bandwidth consumed and the protocols employed. While this form of anomaly detection is useful for detecting new threats, it can also produce false positives when legitimate bandwidth needs exceed a baseline or when baselines are incorrectly designed.

2. Signature-based

It is built on a dictionary of individually recognizable patterns (or signatures) in each exploit's code. When an exploit is detected, its signature is captured and kept in a dictionary of signatures that is constantly developing. Signatures are predefined and preconfigured attack patterns. There are two forms of signature detection for IPS.

Firstly, individual exploits are identified by exploit-facing signatures that activate the distinctive characteristics of a specific attack attempt. The IPS may identify certain exploits by looking for a match in the traffic stream with an exploit-facing signature.

Secondly, vulnerability signatures are those that work on a larger scale and try to detect system vulnerabilities. These signatures safeguard networks from exploit versions that may not have been directly discovered in the wild.

3. Policy-based

This method requires administrators to configure security rules by organizational security requirements and network architecture. An alert is generated and sent to the system administrators when a security policy is violated. Any traffic discovered to be outside of the policy will either cause an alarm or be blocked. Developing a security strategy requires an in-depth understanding of network traffic and is a time-consuming effort.

An algorithm is used in policy-based signatures to assess if an alert should be triggered. Policy-based signature algorithms are typically statistical analyses of internet flow. For example, in a policy-based signature used to identify a port scan, the algorithm raises an alarm when a certain number of distinct ports are scanned on a certain system. Signature algorithms based on policies can be set up to only analyze certain sorts of packets.

What Are the Types of IPS?

There are four primary types of intrusion protection systems:

What Are the Types of IPS

Figure 1. What Are the Types of IPS

1. Wireless Intrusion Prevention System (WIPS)

Wi-Fi is a technical miracle that delivers the utmost in online ease and is almost universally accepted everywhere you travel. However, even 20 years after it entered the mainstream, the technology is still fraught with distinct vulnerability concerns. Many of these concerns can be alleviated by using WIPSs (Wireless Intrusion Prevention Systems).

A wireless intrusion prevention system is a security solution for wireless networks. A WIPS monitors all the radio frequencies in the coverage area of the wireless network and monitors the activities that are not registered in the system. The system detects potentially hazardous behavior on its own and can shut it down automatically. Modern WIPSs frequently go beyond simple frequency analysis, identifying known wireless devices, recording their distinctive signal patterns, and maybe more, depending on the system you pick.

A WIPS checks the MAC addresses of all wireless access points on a network to the known signatures of pre-authorized, known wireless access points and notifies an administrator if there is a mismatch. To avoid MAC address spoofing, certain higher-end WIPS can evaluate the unique radio frequency signatures generated by wireless devices and block unfamiliar radio fingerprints.

2. Network Behavior Analysis (NBA)

As the name implies, this type of intrusion prevention system is based on anomaly detection and searches for deviations from typical behavior in a system or network. This means that a training time is required to profile what is called typical. Inconsistencies are identified as malicious once the training time is completed. While this is useful for identifying new threats, problems may occur if the network was penetrated during the training phase, since malicious activity may be misinterpreted. Furthermore, these security technologies can generate false positives. It is also known as "Behavior Monitoring". Behavioral monitoring technologies examine data from a variety of sources and use machine learning to find trends that may indicate an attack is underway.

The primary goal of this type of IPS is to ensure that no harmful packets are generated and delivered across the internal network. Organizations that use this sort of IPS are always protected from attacks such as DoS (Denial of Service) or any privacy violation-based assault.

3. Host-based Intrusion Prevention System (HIPS)

A host-based intrusion prevention system (HIPS) is used to safeguard sensitive computer systems that hold important data from viruses and other Internet infections. HIPS guards against known and undiscovered threats from the network layer up to the application layer. HIPS monitors a single host for suspicious behavior by reviewing occurrences that occur within that host. To put it another way, a Host Intrusion Prevention System (HIPS) attempts to prevent malware by monitoring the code's behavior. This contributes to the security of your system without requiring a specific vulnerability to be added to a detection update.

A HIPS monitors system calls, application logs, and file-system updates to identify intrusions using a database of system objects monitored (binaries, password files, capability databases, and access control lists). The HIPS maintains each object's properties and generates a checksum for the contents for each item in question. This data is saved in a safe database for subsequent comparison.

4. Network-based Intrusion Prevention System (NIPS)

A network-based intrusion prevention system (NIPS) is used to monitor and safeguard a network's privacy, stability, and accessibility. Its primary functions include safeguarding the network against attacks such as denial of service (DoS) and illegal access. NIPS collects information from the host and network after installation to identify approved hosts, applications, and operating systems on the network. They also record information about regular traffic to detect deviations from the baseline. They can defend against attacks by establishing a TCP connection, restricting bandwidth use, or rejecting packets.

Network Intrusion Prevention Services ("NIPS") are a sophisticated and costly concept that must be carefully and successfully implemented inside a company's infrastructure. It is frequently used in Data Centers with Cloud Hosting providers to give a decent level of cybersecurity assurance on important networks.

Does IPS Protect Against Malware?

Malware is a type of malicious software designed to harm or destroy computers and computer systems. The name "malware" comes from the phrase "malicious software." Malware examples include viruses, worms, Trojan viruses, adware, spyware, etc.

The IPS conducts real-time packet inspection, thoroughly examining each packet that crosses the network. If the IPS identifies malicious or suspicious packets, one of the following steps will be taken:

  • Firstly, it terminates the compromised TCP connection and restricts the offending source IP address or user account from gaining unauthorized access to any application, target hosts, or other network resources.
  • It rewrites the protocol and reconfigures the firewall to avoid a similar attempt in the future.
  • Any malicious material that stays on the network following an attack is removed using a variety of approaches such as repackaging payloads, deleting header information, and removing any infected attachments.

Is Firewall an IPS?

A firewall is a device that serves as a barrier between an organization's internal network and the rest of the internet. Its purpose is to forward some packets while filtering others. A firewall, for example, can be used to filter all incoming packets destined for a single host or server, such as HTTP, or to block access to a specific host or service inside the company.

A firewall is the closest comparison for an IPS. There will be a certain number of rules in a typical company firewall: maybe a hundred, maybe a thousand. The majority of the regulations are "pass" rules, which mean "allow traffic to pass." As a result, when the firewall receives a packet over the internet, it searches its rules for a rule that says "let this packet through." If there are no rules that say "let this packet through" at the end of the list, there is a final "deny" rule: "drop everything else." As a result, the firewall drops the traffic if there is no reason to pass it.

And IPS is similar, but on the inside: it includes hundreds, if not thousands, of rules. The majority of these rules are "deny" rules, which mean "block this known security issue." When a packet arrives at the IPS, it goes through its rule list from top to bottom, seeking a reason to reject it. However, at the bottom of the list is an implied "pass" rule: "allow this packet to pass." As a result, unless there is a cause to drop the traffic, the IPS will let it flow.

What's the Difference Between IDS and IPS?

Intrusion detection systems (IDS) and intrusion prevention systems (IPS) both monitor network traffic for threat signatures or abnormalities. But there are main differences between them are listed below;

  • The main difference is that IDS is a monitoring system, whereas IPS is a control system. IDS system security does not alter the packets but rather checks them extensively against a database for potential threats. The IPS security mechanism prevents any packages from entering the system network.
  • When an intrusion detection system (IDS) scans a network for malicious activity, human intervention is required for the scanned findings to take action to resolve the threats. Meanwhile, IPS works as an autopilot, analyzing network traffic and blocking recognized threats from gaining access to network infrastructure.
  • Intrusion Prevention Systems (IPS) operate between the internal network and the internet. Internet traffic has to flow through the IPS. IDS does not operate inline so internet traffic does not have to pass through it.
  • False-positive alerts in IDS will only result in notifications, however, false positives in IPS may result in the loss of critical data or functionality.

What is the Difference Between Antivirus and IPS?

Here are the main differences between Antivirus and IPS;

  • Antivirus is not the same as an intrusion prevention system (IPS). Antivirus applications do not scan networks since they scan files or objects rather than packets.
  • Antivirus is software. It is not a piece of hardware like an IPS or IDS. It's a security-based program that runs as an application.
  • Antiviruses do not work inside or outside of a network, they are run by being installed on a device like other software.
  • IPS protects the perimeter of a network. An antivirus application is used to protect endpoints or hosts.