Which monitoring methodology will trigger the IDS if any application tries to scan multiple ports?
Signature-based monitoring
Heuristic monitoring
Anomaly-based monitoring
Behavior-based monitoring
The Correct Answer and Explanation is :
The correct answer is Anomaly-based monitoring.
Explanation:
Intrusion Detection Systems (IDS) are designed to monitor network or system activity for malicious or suspicious behavior. They rely on different methodologies to detect potential intrusions. Let’s break down the types mentioned:
- Signature-based monitoring: This method involves detecting known threats by matching network traffic or system behaviors against a predefined database of signatures (patterns) of known attacks. For example, if an attack such as a port scan has been previously observed, its signature will be in the database. However, this method is only effective for detecting known attacks. A port scan that has not been previously observed or is not in the signature database will not trigger an alert.
- Heuristic monitoring: This is a method that involves the use of rules or algorithms to detect potential malicious activities based on certain attributes. Heuristic analysis looks for behaviors that could indicate an attack, but it’s still somewhat based on predefined conditions. Heuristic monitoring may catch some port scanning behavior, but it is not as adaptable or broad as anomaly-based monitoring in terms of detecting unfamiliar attacks.
- Anomaly-based monitoring: This method builds a baseline of what is considered “normal” network or system behavior and then triggers alerts if there is a deviation from this baseline. For instance, if an application suddenly starts scanning multiple ports in a manner that is not typical for that system, anomaly-based IDS would detect this unusual behavior and raise an alert. Anomaly-based systems are highly effective for detecting new or unknown types of attacks, including unfamiliar port scans, because they focus on deviations from normal behavior, rather than known attack signatures.
- Behavior-based monitoring: This is similar to anomaly-based monitoring, but it focuses more specifically on how an application behaves rather than the general network traffic patterns. If the scanning behavior of an application deviates from its typical behavior (such as probing multiple ports unusually quickly), this system would also detect such activities, though it may not be as broad in scope as anomaly-based monitoring.
Conclusion:
Anomaly-based monitoring is the best methodology to detect port scanning behavior, as it can recognize unusual activity based on deviations from normal behavior, including unknown or novel attack patterns like an application scanning multiple ports.