Analysis Methods Performed by Sensors

The sensor performs multiple layers of analysis in real time:

  • Signature-based detection: Traditional Suricata rules (ET Pro + custom) with fast_pattern and rich metadata.

  • Machine learning-based anomaly detection: Random Cut Forests, Isolation Forests (and evaluated alternatives) on protocol features and netflow statistics. Protocol features include DNS entropy/volume, HTTP UA anomalies, and TLS handshake time.

  • Behavioral anomaly detection: RisingWave materialized views for behavioral-based detection.

  • Statistical anomaly detection: Netflow analysis for exfiltration (bytes out/in ratio) and long-duration connections.

  • Protocol anomaly detection: Malformed packets, unusual handshake time, ALPN mismatches.

  • High-fidelity threat intelligence: Real-time match against C2, TI, and OSINT feeds (IPs, domains, URLs, hashes).

Encrypted traffic analysis (performed even without decryption keys):

  • Statistical analysis of netflow (packet/byte ratios, inter-packet time).

  • TLS certificate analysis (validity period, subject/issuer anomalies, chain length).

  • IP analysis and match to threat intelligence (suspicious ASNs, countries, known C2 infrastructure).

  • JA3 and JA4 fingerprint of client and server TLS parameters.