Which term describes misuse-detection-style intrusion detection that relies on anomalies rather than signatures?

Which term describes misuse-detection-style intrusion detection that relies on anomalies rather than signatures?

• A. Anomaly Detection
• B. Signature Recognition
• C. Protocol Anomaly Detection
• D. File System Intrusions

Answer: (A)

Anomaly detection is about spotting unusual or abnormal behavior by comparing current activity to a baseline of what’s considered normal. In misuse-detection-style intrusion detection that relies on anomalies, the system looks for deviations from that normal pattern rather than trying to match known attack signatures. This lets it flag potentially malicious activity even if the exact attack hasn’t been seen before, including new or zero-day exploits. Because it focuses on deviations rather than known patterns, anomaly detection can catch things that signature-based approaches might miss. It’s not limited to a single type of data—network traffic, user behavior, or system calls can all be analyzed for unusual activity. However, it may require careful tuning to reduce false positives. The other options don’t fit as well. Signature recognition, in contrast, relies on known attack patterns alone and wouldn’t describe a method based on deviations from normal behavior. Protocol anomaly detection narrows the scope to anomalies in how protocols behave, which is a form of anomaly detection but not the general term for the approach described. File system intrusions isn’t a detection method name at all.

Anomaly detection is about spotting unusual or abnormal behavior by comparing current activity to a baseline of what’s considered normal. In misuse-detection-style intrusion detection that relies on anomalies, the system looks for deviations from that normal pattern rather than trying to match known attack signatures. This lets it flag potentially malicious activity even if the exact attack hasn’t been seen before, including new or zero-day exploits.

Because it focuses on deviations rather than known patterns, anomaly detection can catch things that signature-based approaches might miss. It’s not limited to a single type of data—network traffic, user behavior, or system calls can all be analyzed for unusual activity. However, it may require careful tuning to reduce false positives.

The other options don’t fit as well. Signature recognition, in contrast, relies on known attack patterns alone and wouldn’t describe a method based on deviations from normal behavior. Protocol anomaly detection narrows the scope to anomalies in how protocols behave, which is a form of anomaly detection but not the general term for the approach described. File system intrusions isn’t a detection method name at all.