{
  "schema_version": "1.0.0",
  "rubric_version": "1.0",
  "license": "CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)",
  "record": {
    "id": "K-0002",
    "slug": "verifier",
    "title": "Verifier",
    "aliases": [],
    "status": "draft",
    "last_reviewed": "2026-09-23",
    "review_interval_days": 90,
    "steward": null,
    "provenance": {
      "drafted_by": "ai",
      "reviewed_by": []
    },
    "risk_flags": [],
    "flags": [],
    "one_liner": "The party that examines evidence supplied by, or collected about, a prover and decides whether the prover's claim holds.",
    "sources": [
      {
        "source": "S-0004",
        "supports": "Verifier defined as an institution, such as another state or an international institution, that assesses the Prover's compliance",
        "locator": "p. 18, fn. 20"
      },
      {
        "source": "S-1603",
        "supports": "Verifier appraises evidence and produces attestation results; Relying Party acts on them",
        "locator": "§4 Terminology"
      },
      {
        "source": "S-0002",
        "supports": "Verifier may be a government body or a third party",
        "locator": "§3.1"
      },
      {
        "source": "S-1606",
        "supports": "soundness: if the statement is false, a verifier following the protocol will not be convinced",
        "locator": "p. 1"
      },
      {
        "source": "S-0029",
        "supports": "Verifier randomly samples and inspects chips and re-runs selected training segments",
        "locator": "§3.1–3.2; §5.1"
      },
      {
        "source": "S-0018",
        "supports": "a malicious verifier may try to exfiltrate confidential information; its devices are verifier-trusted and prover-distrusted",
        "locator": "threat model section"
      }
    ],
    "related": [
      "K-0001",
      "K-0004",
      "K-0018",
      "K-0020"
    ],
    "type": "concept",
    "url": "https://trustbutveri.fyi/concepts/verifier/",
    "source_file": "content/concepts/verifier.md",
    "flags_all": [
      "ai-drafted"
    ],
    "body_markdown": "A verifier is the party that examines evidence from or about a [[K-0001|prover]] and decides whether the prover's claim holds [[S-0004]] [[S-1603]].\n\nUnder an international agreement the verifier may be another state, an international institution, a government body or a third party [[S-0004]] [[S-0002]]. In proof systems, soundness protects the verifier: if a statement is false, a verifier that follows the protocol will not be convinced [[S-1606]]. The IETF remote-attestation architecture splits the role in two: a verifier appraises evidence and produces attestation results, and a separate relying party acts on them [[S-1603]]. In Shavit's framework the verifier randomly samples and physically inspects accelerators, and re-runs selected training segments as in [[M-0006|proof-of-learning]] [[S-0029]]. In low-trust settings the verifier is itself a potential adversary: one system design assumes it may try to exfiltrate the prover's secrets, so the prover distrusts the devices the verifier relies on [[S-0018]].",
    "body_text": "A verifier is the party that examines evidence from or about a prover and decides whether the prover's claim holds [S-0004] [S-1603]. Under an international agreement the verifier may be another state, an international institution, a government body or a third party [S-0004] [S-0002]. In proof systems, soundness protects the verifier: if a statement is false, a verifier that follows the protocol will not be convinced [S-1606]. The IETF remote-attestation architecture splits the role in two: a verifier appraises evidence and produces attestation results, and a separate relying party acts on them [S-1603]. In Shavit's framework the verifier randomly samples and physically inspects accelerators, and re-runs selected training segments as in proof-of-learning [S-0029]. In low-trust settings the verifier is itself a potential adversary: one system design assumes it may try to exfiltrate the prover's secrets, so the prover distrusts the devices the verifier relies on [S-0018].",
    "referenced_by": [
      {
        "id": "M-0025",
        "title": "Confidential multi-party verification",
        "url": "https://trustbutveri.fyi/mechanisms/confidential-multi-party-verification/"
      },
      {
        "id": "M-0015",
        "title": "Memory wiping and proofs of secure erasure",
        "url": "https://trustbutveri.fyi/mechanisms/memory-wiping-and-secure-erasure/"
      },
      {
        "id": "M-0013",
        "title": "Network taps and certifiers",
        "url": "https://trustbutveri.fyi/mechanisms/network-taps-and-certifiers/"
      },
      {
        "id": "M-0006",
        "title": "Proof-of-learning and training-transcript verification",
        "url": "https://trustbutveri.fyi/mechanisms/proof-of-learning/"
      },
      {
        "id": "M-0023",
        "title": "Safeguard attestation",
        "url": "https://trustbutveri.fyi/mechanisms/safeguard-attestation/"
      },
      {
        "id": "M-0001",
        "title": "Sampled inference recomputation",
        "url": "https://trustbutveri.fyi/mechanisms/sampled-inference-recomputation/"
      },
      {
        "id": "M-0017",
        "title": "Tamper evidence for verifier devices",
        "url": "https://trustbutveri.fyi/mechanisms/tamper-evidence-for-verifier-devices/"
      },
      {
        "id": "M-0008",
        "title": "TEE remote attestation for AI workloads",
        "url": "https://trustbutveri.fyi/mechanisms/tee-remote-attestation/"
      },
      {
        "id": "M-0016",
        "title": "Timed challenge-response and memory-occupation challenges",
        "url": "https://trustbutveri.fyi/mechanisms/timed-challenge-response/"
      },
      {
        "id": "M-0004",
        "title": "Zero-knowledge proofs of inference",
        "url": "https://trustbutveri.fyi/mechanisms/zk-proofs-of-inference/"
      },
      {
        "id": "I-0012",
        "title": "Low-trust AI compute verification system overview",
        "url": "https://trustbutveri.fyi/implementations/low-trust-compute-verification-system-overview/"
      },
      {
        "id": "I-0003",
        "title": "zkLLM",
        "url": "https://trustbutveri.fyi/implementations/zkllm/"
      },
      {
        "id": "K-0001",
        "title": "Prover",
        "url": "https://trustbutveri.fyi/concepts/prover/"
      },
      {
        "id": "K-0009",
        "title": "Recomputation",
        "url": "https://trustbutveri.fyi/concepts/recomputation/"
      },
      {
        "id": "K-0018",
        "title": "Threat model",
        "url": "https://trustbutveri.fyi/concepts/threat-model/"
      },
      {
        "id": "K-0010",
        "title": "Zero-knowledge proof",
        "url": "https://trustbutveri.fyi/concepts/zero-knowledge-proof/"
      },
      {
        "id": "O-0205",
        "title": "Oxford Martin AI Governance Initiative",
        "url": "https://trustbutveri.fyi/organizations/oxford-martin-ai-governance-initiative/"
      }
    ]
  }
}