Find where a device goes quiet.
An unattended test bench for OT devices that catches silent failures and replays every one.
Every firmware release needs fresh security evidence. Someone still sits next to the device to restart it.
Now
EN 18031 applies to connected radio devices sold in the EU under the Radio Equipment Directive.
Dec 2027
The Cyber Resilience Act makes security requirements mandatory for products with digital elements sold in the EU.
The gap
Fuzzers find crashes. They miss devices that hang silently, and they rarely keep the input that caused the failure.
How it works
The bench runs the night shift.
Power it like a person would
A relay cuts and restores power on its own, so a hung device gets restarted at 3am without anyone at the bench.
Know when it goes quiet
Protocol heartbeat, response timing, bus activity and current draw are read together. A device that stops answering but still looks powered gets caught.
Replay every failure
Every input is seeded and logged with the traffic around it. A failure only counts once it reproduces, byte for byte.
Hand over evidence, not a bug list
Results map to IEC 62443-4-2 requirements and to the exact firmware hash that was tested.
AI proposes offline. Deterministic code runs the bench.
Certification needs tests that repeat exactly. The ISASecure robustness spec already asks for seeded, replayable runs, so the model never sits in the loop that touches the device.
Propose
A local model drafts test grammars and sorts findings. It runs offline and has no path to the device.
Validate
Deterministic code checks every proposed case against a signed policy before it can run.
Execute
Only the executor touches the device, from a frozen, logged manifest.
Sign off
A person reviews the manifest and the results before anything is reported.
The report a buyer or a notified body can read.
A pre-assessment package: each requirement marked pass, fail or not tested, tied to the firmware hash and the replayable case behind it.
| Requirement | Name | Result | Evidence |
|---|---|---|---|
| CR 3.5 | Input validation | Fail | Case replayed 3 of 3, pcap attached |
| CR 7.1 | Denial of service protection | Fail | Silent hang, recovered by relay cycle |
| CR 3.6 | Deterministic output | Pass | Outputs held during fault |
| CR 7.2 | Resource management | Pass | No degradation over overnight run |
| CR 1.1 | Human user identification | Not tested | Out of scope for this run |
Built for the devices that keep the grid running.
- EV chargers (OCPP 1.6, 2.0.1)
- PLCs and RTUs (Modbus)
- Smart meters and gateways
- Inverters and home batteries
- Grid-edge controllers
Building it with the people who will use it.
If you own security testing or certification for connected devices, I would like to hear how you do it today. Twenty minutes, no pitch.
Talk to Alex