CAIN-42 PBFT quorum-certificate evidence: degraded-network-948b189-2026-09-27
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What: Every quorum certificate held by each replica after 240 s of 'delay 120ms 40ms distribution normal loss 10% duplicate 5% reorder 10% 50%' on all four replicas' mesh traffic. Re-run after the engine upgrade to 948b189, for comparison with degraded-network-2026-09-27.
Classification: MEASURED on the live 4-server cluster cain-mr-02 under packet loss, delay, jitter, duplication and reordering
Generated: 2026-09-27T04:37:15Z
Source commitment: git 948b1895bec0490279aff60b372d158c70722344 (engine 33.4-production-hardened); source is not published.

Verify in about 30 seconds (Python 3.8+, `pip install cryptography`, no CAIN code):

  BASE=https://cainstudio.online/proof/bundle/degraded-network-948b189-2026-09-27/      # or https://mcpgate.online/proof/bundle/degraded-network-948b189-2026-09-27/
                                                             # or https://clawx.click/evidence/degraded-network-948b189-2026-09-27/
  curl -so verify_pbft_qc_bundle.py "$BASE/verify_pbft_qc_bundle.py.txt"
  curl -so PBFT_QC_BUNDLE.json "$BASE/PBFT_QC_BUNDLE.json"
  sha256sum PBFT_QC_BUNDLE.json verify_pbft_qc_bundle.py
    # expect 401686a4a9ad475a09f786d02760b8871336c3da61cc9bfd340b12d3e270f9f9  PBFT_QC_BUNDLE.json
    # expect ba452ce42528f11f7f5235727a65cae25a34072bc52b4711fd72581615d06009  verify_pbft_qc_bundle.py
  python3 verify_pbft_qc_bundle.py PBFT_QC_BUNDLE.json

Or open $BASE/index.html: your browser runs the same checks (WebCrypto Ed25519).

Read the verifier before trusting it: it is about 300 lines. It tampers with a certificate
in seven ways and requires every tampered copy to fail, so a verifier that accepts
everything would not pass.

Not claimed: impairments beyond the stated parameters; flapping links or long partitions (see the partition bundles); latency numbers as a guarantee (one client host); independent operators or providers; third-party review.