{
  "schema_version": "1.0.0",
  "rubric_version": "1.0",
  "license": "CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)",
  "record": {
    "id": "K-0014",
    "slug": "network-tap",
    "title": "Network tap",
    "aliases": [
      "TAP",
      "traffic tap"
    ],
    "status": "draft",
    "last_reviewed": "2026-09-23",
    "review_interval_days": 90,
    "steward": null,
    "provenance": {
      "drafted_by": "ai",
      "reviewed_by": []
    },
    "risk_flags": [],
    "flags": [],
    "one_liner": "A device that copies the traffic on a network link for inspection without disrupting it; proposed for checking what AI data centres compute.",
    "sources": [
      {
        "source": "S-0031",
        "supports": "definition; passive vs active taps; taps capture traffic and commit to it by hashing and timestamping; front-end links most viable; back-end fabric bandwidth, latency and sampling",
        "locator": "sections on definitions, north-south and east-west links"
      },
      {
        "source": "S-0002",
        "supports": "mutually vetted devices intercept inter-chip data and check against declared uses",
        "locator": "§4.2"
      },
      {
        "source": "S-0018",
        "supports": "fixed-function taps generating cryptographic commitments (signed hashes) without transmitting plaintext",
        "locator": "evidence capture"
      }
    ],
    "related": [
      "K-0021",
      "K-0024",
      "K-0019"
    ],
    "type": "concept",
    "url": "https://trustbutveri.fyi/concepts/network-tap/",
    "source_file": "content/concepts/network-tap.md",
    "flags_all": [
      "ai-drafted"
    ],
    "body_markdown": "A network tap is a device that copies the traffic on a network link for inspection without disrupting normal operation [[S-0031]].\n\nPassive taps observe without interfering, for example by optically splitting the light in a fibre; active taps interact with the traffic, for instance by re-timing it or modifying headers to reduce covert channels [[S-0031]]. RAND's verification framework includes mutually vetted devices that intercept data exchanged between accelerators and check it for discrepancies with declared uses [[S-0002]]. In proposed designs such as [[M-0013|network taps and certifiers]], verifier-controlled taps hash and timestamp the traffic as [[K-0024|cryptographic commitments]] rather than exporting plaintext, so that the prover's declarations can later be checked against them [[S-0031]] [[S-0018]]. Cankaya describes taps on the front-end links between a data centre and the outside world as the most viable, because those links carry little bandwidth [[S-0031]]. The back-end fabric between accelerators has far higher [[K-0021|bandwidth]] and strict latency requirements, and may call for random sampling rather than full capture [[S-0031]].",
    "body_text": "A network tap is a device that copies the traffic on a network link for inspection without disrupting normal operation [S-0031]. Passive taps observe without interfering, for example by optically splitting the light in a fibre; active taps interact with the traffic, for instance by re-timing it or modifying headers to reduce covert channels [S-0031]. RAND's verification framework includes mutually vetted devices that intercept data exchanged between accelerators and check it for discrepancies with declared uses [S-0002]. In proposed designs such as network taps and certifiers, verifier-controlled taps hash and timestamp the traffic as cryptographic commitments rather than exporting plaintext, so that the prover's declarations can later be checked against them [S-0031] [S-0018]. Cankaya describes taps on the front-end links between a data centre and the outside world as the most viable, because those links carry little bandwidth [S-0031]. The back-end fabric between accelerators has far higher bandwidth and strict latency requirements, and may call for random sampling rather than full capture [S-0031].",
    "referenced_by": [
      {
        "id": "M-0013",
        "title": "Network taps and certifiers",
        "url": "https://trustbutveri.fyi/mechanisms/network-taps-and-certifiers/"
      },
      {
        "id": "M-0003",
        "title": "Reproducible computation packets",
        "url": "https://trustbutveri.fyi/mechanisms/reproducible-computation-packets/"
      },
      {
        "id": "M-0001",
        "title": "Sampled inference recomputation",
        "url": "https://trustbutveri.fyi/mechanisms/sampled-inference-recomputation/"
      },
      {
        "id": "M-0022",
        "title": "Side-channel suppression for isolated facilities",
        "url": "https://trustbutveri.fyi/mechanisms/side-channel-suppression/"
      },
      {
        "id": "M-0005",
        "title": "Zero-knowledge proofs of training constraints",
        "url": "https://trustbutveri.fyi/mechanisms/zk-proofs-of-training-constraints/"
      },
      {
        "id": "I-0011",
        "title": "AI 2040 inference-only verification stack",
        "url": "https://trustbutveri.fyi/implementations/ai-2040-inference-only-verification-plan/"
      },
      {
        "id": "I-0012",
        "title": "Low-trust AI compute verification system overview",
        "url": "https://trustbutveri.fyi/implementations/low-trust-compute-verification-system-overview/"
      },
      {
        "id": "I-0008",
        "title": "SASH confidential network logger",
        "url": "https://trustbutveri.fyi/implementations/sash-confidential-network-logger/"
      },
      {
        "id": "C-0008",
        "title": "Communication between compute groups is bounded",
        "url": "https://trustbutveri.fyi/claims/bandwidth-is-bounded/"
      },
      {
        "id": "C-0004",
        "title": "This compute runs inference, not training",
        "url": "https://trustbutveri.fyi/claims/inference-not-training/"
      },
      {
        "id": "C-0009",
        "title": "Model weights or data have not left the facility",
        "url": "https://trustbutveri.fyi/claims/weights-have-not-left/"
      },
      {
        "id": "K-0017",
        "title": "Compartmentalization",
        "url": "https://trustbutveri.fyi/concepts/compartmentalization/"
      },
      {
        "id": "K-0024",
        "title": "Cryptographic commitment",
        "url": "https://trustbutveri.fyi/concepts/cryptographic-commitment/"
      },
      {
        "id": "K-0021",
        "title": "Interconnect bandwidth",
        "url": "https://trustbutveri.fyi/concepts/interconnect-bandwidth/"
      },
      {
        "id": "K-0022",
        "title": "Weight exfiltration",
        "url": "https://trustbutveri.fyi/concepts/weight-exfiltration/"
      }
    ]
  }
}