An advanced persistent threat (APT) is a sophisticated, long-term, multi-staged attack. Nation-state groups or well-organized criminal enterprises typically orchestrate them.
An IPS tool sits inline and behind your firewall, scanning all incoming traffic for signs of threats. It uses signature-based and anomaly detection for patterns and performance level deviations.
Real-time Detection
Unlike an IDS, which alerts when it detects suspicious activity, IPS takes action to thwart attacks in real time. It can include reporting detected threats, blocking traffic from a source, or even resetting connections to halt attack execution.
It is done through a combination of signature-based detection and statistical anomaly-based detection. The former uses a database of uniquely identifiable patterns found in each exploit’s code, while the latter randomly samples network traffic and compares them to performance levels that are normal for your organization’s environment.
It prevents attackers from gaining a foothold in your system and allows security operations teams to act quickly to halt attacks before they do damage. IPS also integrates with other security solutions to enhance detection capabilities and provide more comprehensive protection. For example, a modern IPS can be integrated with threat intelligence systems that use machine learning to identify zero-day attacks and new malware. It can also be connected to alert management systems that elevate notifications as loud, audible, alert-until-read messages to accelerate response times and avoid missing a genuine attack. Moreover, a cloud-native IPS eliminates hardware limitations that limit performance and scalability and allows unlimited compute resources to support traffic decryption. It is crucial as more than half of all Internet traffic is now encrypted. It enables an IPS to quickly decrypt and inspect encrypted packets without disrupting business as usual.
Automated Responses
Many of the threats that IPS tools detect can be prevented from doing damage or spreading by automated responses and mitigation capabilities. It gives IPS solutions a distinct edge over IDS solutions.
A typical IPS can identify malicious activity in real-time by monitoring network traffic and comparing it to known attack signatures (updated constantly). It is called signature-based detection and works like anti-virus software scans files. When an attacker attempts to exploit a vulnerability in your systems, the IPS detects that activity and alerts you.
The IPS then takes action based on the severity of the threat. It may include alerting you, dropping suspicious packets, closing ports, or resetting connections to prevent further attacks and mitigate the impact of an incident. In the millisecond world of computer activity, an administrator can’t react to every alert that a traditional IDS generates, so this preventive capability gives an IPS a substantial advantage over IDS solutions.
Depending on the security solution and configuring, the IPS may also use attack pattern analysis, anomaly-based detection, or network behavior analytics to detect threats. This means that attackers use sophisticated malware like Cobalt Strike and command-and-control channels to steal data and infect additional machines, part of what attacks are detected by an IPS.
Reduce False-Positive Alerts
While IPSs are known for their ability to detect and stop attacks, they can also produce false positive alerts that security professionals must sift through. It can be a considerable burden on already overburdened security teams, and it can make them unable to focus on real threats and other critical tasks.
The primary way to reduce false positives is using advanced heuristics to identify suspicious traffic patterns. For example, heuristics can be used to identify patterns, such as using older versions of SSL or protocols that rely on weak ciphers. Alternatively, the IPS can be configured to only report on packet sequences that are most likely to be malicious.
A modern IPS should be designed to support frequent updates that enable it to detect new exploits and attack campaigns as quickly as possible. Additionally, the IPS should be able to decrypt encrypted traffic streams to eliminate latency and ensure that it can inspect and protect data.
Unlike IDS, which merely detects bad traffic and creates an alert to notify security teams, an IPS can prevent the threat from entering the network. Depending on the solution, this might include dropping packets, blocking traffic, or terminating connections. Some IPS technologies also monitor TLS-encrypted traffic flows, which may be essential for businesses with significant amounts of encrypted data.
Scalability
Unlike intrusion detection systems (IDS), software tools that monitor for malicious activities and must alert human administrators when they find signs of an attack, an IPS can immediately thwart bad actors. It can be as simple as dropping a malicious packet or blocking future traffic from the offending IP address or port. The benefit is that this is done without disrupting legitimate network traffic.
An IPS can filter other security solutions, such as firewalls and anti-virus software. It can help them operate more efficiently by reducing the time they must spend monitoring network activity for threats. Additionally, an IPS can detect and block threats that may go undetected by these other solutions.
However, this is not to say that an IPS does not require regular maintenance and updates. As new threats emerge and exploits evolve, an IPS needs frequent signature and patch updates to be aware of these changes and ensure that it can identify them.
