# AI verification proposal

A proposal built with the Proposal Explorer of the AI Verification Tech Map (https://trustbutveri.fyi/), from its records of 2026-10-08. Interactive version: https://trustbutveri.fyi/explorer/?mechanisms=M-0022,M-0009,M-0016&hide=training

How to read it: a claim is something one party wants to verify about another's AI hardware or software. A mechanism is a general technique for verifying claims; it is "aimed at" a claim when that is its direct purpose, and "supporting" when it contributes without being aimed at it. A claim is addressed when a mechanism in the proposal is aimed at it and is not excluded by the filters; addressed does not mean verified, so check that mechanism's readiness and open flaws. Readiness levels R0 to R4 describe one record's public evidence for its assessed use and are never combined. Definitions: https://trustbutveri.fyi/about/methodology/ (roles, properties and flaws) and https://trustbutveri.fyi/about/readiness/ (readiness levels).

## Filters

Filters apply to mechanisms only and describe the setting the proposal is for.

- **Keep hidden from the verifier: training data.** Removes mechanisms that show the asset to the verifier. Conditional or unspecified exposure stays with a note and needs checking against the privacy requirement. Model weights: the checked model's parameters. Inputs and outputs: the requests a deployed model serves and its responses. Training data: what a model was trained on. Each mechanism's exposure is the editors' reading of its record: shown, depends on the design (kept, with a note), hidden, not involved, or unspecified for a selected implementation. Code and configuration are not covered yet.

24 of 25 mechanisms on the map pass these filters.

## Overview

One row per mechanism, read from its record. Open flaws: critical / significant / minor. The last three columns are the editors' reading of what the verifier sees.

| Mechanism | Readiness | Prover | Attack testing | Hardware | Open flaws | Weights | Inputs and outputs | Training data |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Side-channel suppression for isolated facilities | R1 | Adversarial | Analysis | Retrofit device | 0 / 3 / 0 | not involved | not involved | not involved |
| Hardware-enabled guarantees (flexHEG) and guarantee processors | R1 | Adversarial | Analysis | New chip design | 0 / 6 / 0 | hidden | hidden | hidden |
| Timed challenge-response and memory-occupation challenges | R2 | Adversarial | Analysis | None | 0 / 1 / 1 | not involved | not involved | not involved |

## Claims

No claims chosen.

## Mechanisms

### Side-channel suppression for isolated facilities

Shielding, filtering, jamming and inspecting an AI facility to limit hidden physical communication around monitored network links. ([Side-channel suppression for isolated facilities](https://trustbutveri.fyi/mechanisms/side-channel-suppression/))

- Assessment: mechanism family.
- Readiness: R1 Proposed, assessed for bounding physical covert channels out of a verified enclosure.
- Claims in this proposal: none of them.
- Threat model: adversarial prover. Hardware: retrofit device. Prover cooperation: partial. Attack testing: analysis. Category: Off-chip devices & sensors.
- What the verifier sees: model weights not involved; inputs and outputs not involved; training data not involved. Shields and filters a facility; it does not handle model data.

### Hardware-enabled guarantees (flexHEG) and guarantee processors

Proposed chip add-ons, a guarantee processor inside a tamper-protected enclosure, that would check and enforce agreed rules on how AI accelerators are used. ([Hardware-enabled guarantees (flexHEG) and guarantee processors](https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/))

- Assessment: mechanism family.
- Readiness: R1 Proposed, assessed for checking and enforcing training-compute limits on chips, against adversaries up to states.
- Claims in this proposal: none of them.
- Threat model: adversarial prover. Hardware: new chip design. Prover cooperation: required. Attack testing: analysis. Category: On-chip & hardware-enabled.
- What the verifier sees: model weights hidden; inputs and outputs hidden; training data hidden. The guarantee processor sees the chip's traffic inside a sealed enclosure and reports only whether rules were kept.

### Timed challenge-response and memory-occupation challenges

A verifier sends unpredictable questions that a device can answer in time only if it holds specified data, or dedicates specified resources, locally. ([Timed challenge-response and memory-occupation challenges](https://trustbutveri.fyi/mechanisms/timed-challenge-response/))

- Assessment: mechanism family.
- Readiness: R2 Demonstrated, assessed for detecting whether a GPU is doing other work.
- Claims in this proposal: none of them.
- Threat model: adversarial prover. Hardware: none. Prover cooperation: required. Attack testing: analysis. Category: Cryptographic & computational.
- What the verifier sees: model weights not involved; inputs and outputs not involved; training data not involved. Uses verifier-chosen challenges; it does not handle model data.


## Properties

**Built for an adversarial prover**

- Side-channel suppression for isolated facilities
- Hardware-enabled guarantees (flexHEG) and guarantee processors
- Timed challenge-response and memory-occupation challenges

**No new hardware needed**

- Timed challenge-response and memory-occupation challenges


## Attack testing

Published attempts to break a system, including those that found failures. Testing history does not establish that open flaws are resolved.

**Testing history**

- Side-channel suppression for isolated facilities: Analysis
- Hardware-enabled guarantees (flexHEG) and guarantee processors: Analysis
- Timed challenge-response and memory-occupation challenges: Analysis


## Limits

**Open significant flaws**

- Supply-chain implants may evade inspection (theoretical argument, in Side-channel suppression for isolated facilities; https://trustbutveri.fyi/mechanisms/side-channel-suppression/#flaw-1) [1]. Cankaya identifies malicious hardware embedded deep in purchased components as a residual risk that visual inspection and disassembly may not catch. He notes that radiographic examination under high-security standards could mitigate it.
- Openings for airflow, power and optics weaken shielding (theoretical argument, in Side-channel suppression for isolated facilities; https://trustbutveri.fyi/mechanisms/side-channel-suppression/#flaw-2) [1]. Cankaya notes that keeping attenuation high while passing high-power airflow, cabling and optical links adds complexity beyond existing shielded-enclosure specifications.
- Inspection assumptions may not hold (open question, in Side-channel suppression for isolated facilities; https://trustbutveri.fyi/mechanisms/side-channel-suppression/#flaw-3) [1]. The design's statistical argument assumes that visual or disassembly inspection catches every flaw that is present in a sampled unit. Cankaya is unsure whether destructive teardowns are defence-dominant or offence-dominant.
- State attackers can likely defeat current secure enclosures (theoretical argument, in Hardware-enabled guarantees (flexHEG) and guarantee processors; https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/#flaw-1) [3][5]. The flexHEG authors write that "nation-state attackers can likely compromise the best current secure enclosures", and that the marginal cost of circumvention per device is hard to estimate. RAND similarly judges that anti-tamper measures "would not be insurmountable for a determined and well-resourced adversary", although they raise costs and can reveal tampering.
- Firmware-only retrofits rely on Secure Boot, which fault injection can bypass (theoretical argument, in Hardware-enabled guarantees (flexHEG) and guarantee processors; https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/#flaw-2) [3]. Part II notes that the most common attack on Secure Boot replaces the firmware and applies a voltage glitch while the signature is being checked. It also notes that sophisticated actors may use microprobing or laser voltage probing to read key registers.
- Many important rules cannot be checked on-chip (theoretical argument, in Hardware-enabled guarantees (flexHEG) and guarantee processors; https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/#flaw-3) [2][4]. Malicious intent "is not a technical property observable on-chip", and misuse depends on what is done with a computation's results. A guarantee processor cannot easily tell whether a network is the whole system or one expert in a mixture-of-experts system. Part III judges that a fully local ruleset "may not be entirely feasible" for the same reason.
- FLOP accounting can be laundered through external data (theoretical argument, in Hardware-enabled guarantees (flexHEG) and guarantee processors; https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/#flaw-4) [3]. Results of earlier or parallel workloads could be hidden in the "external data" fed to a device, which would falsify the total FLOP count unless the inputs are explained or time delays are imposed.
- Supply-chain diversion and hidden backdoors (open question, in Hardware-enabled guarantees (flexHEG) and guarantee processors; https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/#flaw-5) [3][4]. Components could be diverted before a guarantee processor is added, and backdoors could be introduced during design or manufacturing. Open-source designs and physical scans of randomly selected chips are proposed as countermeasures. Part III proposes international oversight of production and extensive testing of a random sample of finished devices.

  Related mechanism: Chip registries and manufacturing records (R1, not in the proposal). Records each chip's identity and owner from the fab onwards, which bears on diversion before a guarantee processor is fitted. It does not address hidden backdoors.
- Coverage stops at flexHEG-equipped chips (open question, in Hardware-enabled guarantees (flexHEG) and guarantee processors; https://trustbutveri.fyi/mechanisms/flexheg-guarantee-processors/#flaw-6) [2][4]. Motivated actors will always be able to use some compute that is not flexHEG-equipped. Recalling existing consumer GPUs would likely be impractical, and reaching perfect coverage, or conclusively proving that no secret government data centres exist, would be "practically quite difficult".

  Related mechanism: Chip registries and manufacturing records (R1, not in the proposal). Accounts for which chips exist and who holds them.

  Related mechanism: Remote detection of data centres (R1, not in the proposal). Looks for undeclared facilities that hold other chips.
- Remote memory narrows the timing margin (theoretical argument, in Timed challenge-response and memory-occupation challenges; https://trustbutveri.fyi/mechanisms/timed-challenge-response/#flaw-2) [8]. Data-centre remote memory access returns in about 1–2 µs, against about 70–200 ns for local DRAM. The MIRI overview says verification of memory saturation depends on ruling out remote access by latency or physical disconnection. It adds that pre-staging data is ruled out only by unpredictable, capacity-filling challenges.

  Related mechanism: Bandwidth limits and compartmentalization (R2, not in the proposal). Physical disconnection is proposed to exclude remote memory between the separated groups during a challenge. It depends on the isolation boundary being enforced.

**Open minor flaws**

- Error rates not quantified (open question, in Timed challenge-response and memory-occupation challenges; https://trustbutveri.fyi/mechanisms/timed-challenge-response/#flaw-3) [10]. Monfared et al. show separable timing distributions but do not define thresholds or statistical tests, so false-positive and false-negative rates are not quantified.

**Not yet demonstrated**

- Side-channel suppression for isolated facilities: R1 Proposed, assessed for bounding physical covert channels out of a verified enclosure
- Hardware-enabled guarantees (flexHEG) and guarantee processors: R1 Proposed, assessed for checking and enforcing training-compute limits on chips, against adversaries up to states

**Need new chip designs**

- Hardware-enabled guarantees (flexHEG) and guarantee processors


## Possible additions

Mechanisms on the map, not in the proposal, that the records connect to an unaddressed or partly addressed claim, an open flaw or a dependency. Pointers, not recommendations: each brings its own readiness level and flaws, and none is claimed to close a flaw.

- **Bandwidth limits and compartmentalization** (R2 Demonstrated, assessed for monitoring inter-node traffic with operator-run software on four GPUs)
  - Bears on the open significant flaw "Remote memory narrows the timing margin" in Timed challenge-response and memory-occupation challenges. Physical disconnection is proposed to exclude remote memory between the separated groups during a challenge. It depends on the isolation boundary being enforced.
  - Timed challenge-response and memory-occupation challenges waits on it: Outside help, such as remote memory, must be excluded during challenges.
- **Chip registries and manufacturing records** (R1 Proposed, assessed for a checkable record of which chips were made and who declared owning them)
  - Bears on the open significant flaw "Supply-chain diversion and hidden backdoors" in Hardware-enabled guarantees (flexHEG) and guarantee processors. Records each chip's identity and owner from the fab onwards, which bears on diversion before a guarantee processor is fitted. It does not address hidden backdoors.
  - Bears on the open significant flaw "Coverage stops at flexHEG-equipped chips" in Hardware-enabled guarantees (flexHEG) and guarantee processors. Accounts for which chips exist and who holds them.
  - Hardware-enabled guarantees (flexHEG) and guarantee processors waits on it: Governing all relevant chips depends on knowing where they are, through chip registries and detection of undeclared facilities.
- **Remote detection of data centres** (R1 Proposed, assessed for finding undeclared data centres above an agreed compute threshold)
  - Bears on the open significant flaw "Coverage stops at flexHEG-equipped chips" in Hardware-enabled guarantees (flexHEG) and guarantee processors. Looks for undeclared facilities that hold other chips.
- **Tamper evidence for verifier devices** (R2 Demonstrated, assessed for detecting probing of proposed verifier hardware, using server and electronics prototypes as evidence)
  - Hardware-enabled guarantees (flexHEG) and guarantee processors waits on it: State-level attackers who hold the hardware can likely compromise the best current secure enclosures.
- **TEE remote attestation for AI workloads** (R3 In production, assessed for showing which software ran to a party that distrusts the operator holding the hardware)
  - Hardware-enabled guarantees (flexHEG) and guarantee processors depends on it.


## Dependencies

**Missing prerequisites**

- TEE remote attestation for AI workloads (R3 In production, assessed for showing which software ran to a party that distrusts the operator holding the hardware), needed by Hardware-enabled guarantees (flexHEG) and guarantee processors
- Chip registries and manufacturing records (R1 Proposed, assessed for a checkable record of which chips were made and who declared owning them), needed by Hardware-enabled guarantees (flexHEG) and guarantee processors

**Blockers**

- Side-channel suppression for isolated facilities: No prototype or red-team exists; the design is a first-pass viability study. (adversarial validation) [1]
- Side-channel suppression for isolated facilities: Volume costs of TEMPEST-grade power-line filters are uncertain, because existing products are mostly made to order. (performance & compatibility) [1]
- Hardware-enabled guarantees (flexHEG) and guarantee processors: Integrated flexHEG needs substantial help from the accelerator manufacturer, and the authors estimate 3.7–7.9 years, from when the manufacturer starts work, for such hardware to displace other accelerators in frontier development. (access & governance) [3]
- Hardware-enabled guarantees (flexHEG) and guarantee processors: State-level attackers who hold the hardware can likely compromise the best current secure enclosures. (hardware trust; waits on Tamper evidence for verifier devices) [3][5]
- Hardware-enabled guarantees (flexHEG) and guarantee processors: Rival states would need to trust the design and manufacture of guarantee processors and enclosures, for example through open design, redundant processors from each side or oversight of production. (hardware trust) [2][4]
- Hardware-enabled guarantees (flexHEG) and guarantee processors: Restricting future rule updates would need a formal language for rules, which the authors judge most likely infeasible for early flexHEG versions. (protocol soundness) [2]
- Hardware-enabled guarantees (flexHEG) and guarantee processors: Governing all relevant chips depends on knowing where they are, through chip registries and detection of undeclared facilities. (coverage & hidden compute; waits on Chip registries and manufacturing records) [4]
- Timed challenge-response and memory-occupation challenges: No network-level memory challenge across data-centre servers has been demonstrated. (adversarial validation) [8]
- Timed challenge-response and memory-occupation challenges: Challenges that fill memory displace workloads; filling a pod's volatile memory takes tens of minutes and SSDs take hours. (performance & compatibility) [8][10]
- Timed challenge-response and memory-occupation challenges: Outside help, such as remote memory, must be excluded during challenges. (coverage & hidden compute; waits on Bandwidth limits and compartmentalization) [8]


## What the verifier sees

- Model weights: shown by none; depends on the design for none; hidden by Hardware-enabled guarantees (flexHEG) and guarantee processors; not involved in Side-channel suppression for isolated facilities and Timed challenge-response and memory-occupation challenges; unspecified for none.
- Inputs and outputs: shown by none; depends on the design for none; hidden by Hardware-enabled guarantees (flexHEG) and guarantee processors; not involved in Side-channel suppression for isolated facilities and Timed challenge-response and memory-occupation challenges; unspecified for none.
- Training data: shown by none; depends on the design for none; hidden by Hardware-enabled guarantees (flexHEG) and guarantee processors; not involved in Side-channel suppression for isolated facilities and Timed challenge-response and memory-occupation challenges; unspecified for none.

## Implementations

- Side-channel suppression for isolated facilities: [AI 2040 inference-only verification stack](https://trustbutveri.fyi/implementations/ai-2040-inference-only-verification-plan/) (R1, proposed architecture); [Low-trust AI compute verification system overview](https://trustbutveri.fyi/implementations/low-trust-compute-verification-system-overview/) (R1, proposed architecture); [RAND secure inference data center (SIDC) design](https://trustbutveri.fyi/implementations/rand-secure-inference-data-centers/) (R1, proposed architecture)
- Hardware-enabled guarantees (flexHEG) and guarantee processors: none on the map
- Timed challenge-response and memory-occupation challenges: [Data-centre memory challenging](https://trustbutveri.fyi/implementations/data-centre-memory-challenging/) (R1, proposed architecture); [GPU contention probes](https://trustbutveri.fyi/implementations/gpu-contention-probes/) (R2, research prototype); [Low-trust AI compute verification system overview](https://trustbutveri.fyi/implementations/low-trust-compute-verification-system-overview/) (R1, proposed architecture); [SAGE](https://trustbutveri.fyi/implementations/sage-gpu-attestation/) (R2, research prototype); [VRAM-residency challenge](https://trustbutveri.fyi/implementations/vram-residency-challenge/) (R2, research prototype)

## Sources

1. Suppressing Side Channels in an Untrusted Data Center via Retrofitted Defenses, N. Cankaya (2026). https://techgov.intelligence.org/blog/suppressing-side-channels-in-an-untrusted-data-center-via-retrofitted-defenses
2. Flexible Hardware-Enabled Guarantees for AI Compute, J. Petrie et al. (2025). https://arxiv.org/abs/2506.15093
3. Technical Options for Flexible Hardware-Enabled Guarantees, J. Petrie & O. Aarne (2025). https://arxiv.org/abs/2506.03409
4. International Security Applications of Flexible Hardware-Enabled Guarantees, O. Aarne & J. Petrie (2025). https://arxiv.org/abs/2506.15100
5. Hardware-Enabled Governance Mechanisms: Developing Technical Solutions to Exempt Items Otherwise Classified Under Export Control Classification Numbers 3A090 and 4A090, G. Kulp et al. (2024). https://www.rand.org/pubs/working_papers/WRA3056-1.html
6. Secure, Governable Chips: Using On-Chip Mechanisms to Manage National Security Risks from AI & Advanced Computing, O. Aarne et al. (2024). https://www.cnas.org/publications/reports/secure-governable-chips
7. Hardware-Enabled Mechanisms for Verifying Responsible AI Development, A. O'Gara et al. (2025). https://arxiv.org/abs/2505.03742
8. A System Overview for Near-Term, Low-Trust AI Compute Verification, N. Cankaya (2026). https://intelligence.org/wp-content/uploads/2026/06/A-system-overview-for-near-term-low-trust-AI-compute-verification.pdf
9. Verification Plan, R. Dean (2026). https://ai-2040.com/supplements/verification-plan
10. Timing and Memory Telemetry on GPUs for AI Governance, S. K. Monfared et al. (2026). https://arxiv.org/abs/2602.09369
11. SAGE: Software-based Attestation for GPU Execution, A. Ivanov et al. (2023). https://www.usenix.org/conference/atc23/presentation/ivanov
12. SWATT: SoftWare-based ATTestation for Embedded Devices, A. Seshadri et al. (2004). https://netsec.ethz.ch/publications/papers/swatt.pdf
13. Proofs of Space, S. Dziembowski et al. (2015). https://eprint.iacr.org/2013/796
14. Secure Code Update for Embedded Devices via Proofs of Secure Erasure, D. Perito & G. Tsudik (2010). https://link.springer.com/chapter/10.1007/978-3-642-15497-3_39
15. Software-Based Memory Erasure with Relaxed Isolation Requirements, S. Bursuc et al. (2024). https://ieeexplore.ieee.org/document/10664348/
16. On the Difficulty of Software-Based Attestation of Embedded Devices, C. Castelluccia et al. (2009). https://s3.eurecom.fr/docs/ccs09_Castelluccia.pdf
17. Refutation of "On the Difficulty of Software-Based Attestation of Embedded Devices", A. Perrig & L. van Doorn (2010). https://netsec.ethz.ch/publications/papers/perrig-ccs-refutation.pdf
