Jay, a network administrator, was monitoring traffic flowing through an IDS. Unexpectedly, he received an event triggered as an alarm, although there is no active attack in progress. Identify the type of IDS alert Jay has received in the above scenario.

A false positive alert occurs when an Intrusion Detection System (IDS) incorrectly flags benign activity as malicious. In the given scenario, the IDS triggered an alarm, which is a "positive" indication of an attack. However, the administrator confirmed that no actual attack was in progress, making the alarm "false." This type of error is a common challenge in IDS management, as a high rate of false positives can lead to alert fatigue and may cause security personnel to overlook genuine threats.

A. True negative alert: This is the desired state for normal traffic, where no attack occurs and no alarm is generated. The scenario explicitly states an alarm was triggered.
C. True positive alert: This is the ideal outcome for a real attack, where the IDS correctly identifies malicious activity and generates an alarm. The scenario states there was no attack.
D. False negative alert: This is a critical failure where a real attack occurs, but the IDS fails to detect it and does not generate an alarm. The scenario describes an alarm.

1. National Institute of Standards and Technology (NIST). (2007). Guide to Intrusion Detection and Prevention Systems (IDPS) (Special Publication 800-94). Section 4.2, "Accuracy," p. 37. The document defines a False Positive as: "An alert that indicates that an attack is in progress or that a system has been compromised, when in fact the traffic was benign and no attack took place."

2. MIT OpenCourseWare. (2014). 6.857 Computer and Network Security, Fall 2014. Lecture 15: Intrusion Detection. Slide 10, "IDS Evaluation." The lecture notes define a "False Alarm (False Positive)" as when the "System says 'attack', but it's not."

3. Garcia-Teodoro, P., Diaz-Verdejo, J., Maciá-Fernández, G., & Vázquez, E. (2009). Anomaly-based network intrusion detection: Techniques, systems and challenges. Computers & Security, 28(1-2), 18–28. Section 2.2, "Evaluation," p. 20. The paper defines a false positive as an event where the system "will produce an alarm for a legitimate action." (DOI: https://doi.org/10.1016/j.cose.2008.08.003)