Compute verification
Inspection Sampling
Designing a chip inspection
An inventory lists each chip and where it should be. Inspectors can choose entries at random and check whether the chips are present and correctly identified. Set the number of errors in the inventory and the access inspectors receive to calculate the chance that their sample includes an error.
Hypothetical inventory
7,200 listed chips; at least 25 discrepancies; 10 chips off limits.
10 of the 25 discrepancies could be among the chips off limits, leaving at least 15 in the accessible inventory.
1,023 chips
633 with unrestricted access
91.7%
chance of selecting at least one missing or misidentified chip
with 1,100 sampled from 7,190 accessible chips
At this sample size, more than 11 chips off limits would put the chance below 90%.
Investigating diversion or prohibited training
CNAS proposes random selection to investigate chip diversion; Shavit proposes it to investigate prohibited training. Checking a chip’s location requires evidence of possession. Checking its use requires records of computation.
Fist and Grunewald · CNAS
Investigate chip diversion: select IDs from an ownership registry, then check the requested chips’ identity and signs of tampering. The proposed mail-in option also checks shipment receipts.
A failed check prompts investigation of the owner or previous owners. The registry needs updates when chips are sold, lost or destroyed. (Technical annex, 2023)
Yonadav Shavit
Investigate prohibited training: inspect sampled chips’ serial numbers, activity logs and logging hardware. Compare logged weight-snapshot fingerprints with the operator’s training records.
This proposed system depends on trustworthy logging and a way to verify the training records. Sampling a chip alone does not establish which training run it took part in. (§§3.1–3.2, 2023)
The calculator covers inventory checks: the chance that selected entries include an error, which inspectors must then establish. Shavit’s training-monitoring calculation also accounts for how often chips save records of model weights and how often inspectors sample them (§3.2).
Challenge-inspection rules
MIRI’s draft draws on the Chemical Weapons Convention, but changes the vote required to launch a challenge inspection. In the proposed US–China Council, either country could withhold consent to an inspection of itself.
Approval
The Executive Council must agree by consensus. It initially consists of the US and China. (X.3(b); III.3)
Preparations begin on a valid request. Stopping them takes three quarters of the Council; the requesting and inspected states cannot participate in that decision. (IX.14–17)
Time to act
The host must grant access within 24 hours of the Council calling the inspection. Surveillance is permitted during that interval. (X.3(c))
The Council has 12 hours to reject a request as frivolous, abusive or outside the Convention’s scope. Its deliberations cannot delay the inspection. (IX.16–17)
Recipients of the findings
The technical body supplies the US and China with all information it receives or generates, including inspection results. (X.4(b))
All States Parties receive the final report, including the inspectors’ assessment of access and cooperation. (IX.21)
The draft also requires both parties to approve the inspection team and caps challenge inspections in any one Party’s territory at 20 a year, changeable by Council consensus (X.3(d–e)). The CWC’s managed-access provisions appear in Part X of its Verification Annex.