Nw Investigation Techniques

Operational Problems

Evidence Collection

Technical Evidence Sources

Logs: application (timestamp correlation) | system/infrastructure | database | network traces

Metrics: performance/resource utilization | error rates/response time trends | user behavior/transaction patterns | infrastructure health/capacity

Configuration: system/deployment settings | code changes/VCS history (git log, blame) | env vars/dependencies | security/access controls

Evidence Validation

1. Cross-reference: verify from multiple independent sources
2. Timestamp validation: confirm event sequence accuracy
3. Completeness check: identify data gaps/corruption
4. Correlation vs causation: distinguish co-occurrence from causation

Analysis Techniques

Quantitative

• Trend: time series of metrics, error pattern frequency
• Distribution: response time percentiles, error rate across components
• Pattern recognition: log anomalies, behavior patterns, error clustering

Qualitative

• Timeline reconstruction: detailed incident timeline, correlate changes with symptoms
• Process analysis: workflow disruptions, communication flow, decision chains
• Environmental: recent changes, system load, external factors, related incidents

Solution Design Patterns

Immediate Mitigations (restore service)

Quick fixes | workarounds to minimize impact | emergency procedures | monitoring enhancements

Permanent Fixes (prevent recurrence)

Architecture modifications | code quality/defensive programming | config management/environment consistency | testing/validation improvements

Early Detection (catch faster)

Leading indicators | anomaly detection/predictive alerting | automated quality gates | threshold tuning from learnings

Solution Prioritization Matrix