Measuring SIRT performance¶
Metrics help a SIRT understand its efficiency, identify bottlenecks, and continuously improve. A lean, agile SIRT focuses on actionable measures rather than generating endless reports. The following table summarises the most important metrics and what they mean in practice.
Metric |
Definition |
Meaning |
|---|---|---|
Detection success |
Number of alerts by department, team, or site. |
Shows how effective your detection solutions are. If the SOC is not generating the majority of alerts, your SIRT may be missing inputs or relying on inadequate sources. |
Detection to decision |
Time taken for activity to be detected and processed through the system to determine if action is required. |
Measures the efficiency of analysts, detection tools, and SIEM. Shorter times indicate smoother alert handling and more responsive incident recognition. |
Decision speed |
Time taken to make a decision, including coordination and gathering relevant stakeholders. |
Decision-making depends on queue length and complexity of investigation. Faster decisions reduce risk exposure but require clear roles and pre-planned processes. |
False positive rates |
Percentage of alerts that, upon investigation, are revealed not to be valid threats. |
High false positives erode confidence in tools, distract analysts, and can hide true issues. Feedback loops to reduce false positives are essential. The only thing worse than a false positive is an overlooked false negative. |
Time to mitigation / containment |
Time from detection to identifying impact, determining response, and implementing mitigation or containment actions. |
Trends over time reveal strengths and weaknesses. These numbers guide investment in automation, remediation tools, and additional protective measures. |
Tips¶
Track metrics consistently: regular reporting, even in small teams, builds awareness and accountability.
Focus on trends rather than single incidents: variations are normal, patterns reveal actionable insights.
Combine quantitative metrics with qualitative observations: analyst experience, workflow bottlenecks, and tool limitations are just as important.
Use metrics to drive improvement, not punishment: a lean SIRT thrives on learning and iteration.
Example¶
If your decision speed is consistently slow for certain alert types, you might improve it by refining workflows, adding playbook steps, or pre-identifying stakeholders for faster escalation.