AI Cyber Defense / Network detection, DNS and egress analytics
AI Cyber Defense: Detect unexpected protocol use on allowed ports
Require service identity and destination intent in egress policy. Investigate protocol mismatches with host context and retain unknown classification as its own state.
Environment and inputs: Network detection and response using resolver logs, proxy metadata, flow records and optional Zeek or Suricata sensors.
Scenario and goal
A service can tunnel an unexpected protocol through a port that an ACL permits.
Why it matters
For this scenario, expect behavior to vary across destinations, timing and client software. Network metadata supports a hypothesis, while endpoint and identity records often explain the actor and purpose. Account for encryption, sampling and sensor placement before interpreting absence. A statistical anomaly, protocol fingerprint or unfamiliar domain should remain a supporting observation until its consequence and business context are established.
Evidence to collect
Compare network protocol classification, server inventory and endpoint process ownership; classification can fail on partial or encrypted traffic.
Validate with an authorized exercise
Replay normal HTTPS metadata and a harmless mismatched-protocol fixture; verify the mismatch reaches review while unknown encrypted traffic is not mislabeled with fabricated protocol details.
Rollout and checks
Preserve event time, source tuple, sensor identity and the original record identifier for every decisive observation. Verify clock alignment and collection health before joining sources. Compare a representative benign workload with the suspected behavior in a lab or stored-event replay. Adjust a detection only after documenting which observed distinction justifies the change.
Scope and limits
This guide proposes a defensive test; it is not a tested production design. Check platform support and local requirements. References explain the mechanisms but do not certify the design. Behavior alone does not prove AI involvement.