{
  "schema_version": "1.3.0",
  "slug": "how-should-an-instance-treat-a-byzantine-equivocation-that-is-invisible-to-two-thirds-of-the-quorum-the-cross-organizational-equivocation-detection-ga",
  "title": "How should an instance treat a Byzantine equivocation that is invisible to two-thirds of the quorum: the cross-organizational equivocation-detection gap",
  "date_of_record": "2026 November 10",
  "scope": "Applies to BFT consensus deployments where voting power is partitioned across organizational trust domains and where message authentication is pairwise (per-link keys or per-domain channels) rather than globally broadcast. Does not apply to single-organization clusters with a shared broadcast medium, nor to protocols that mandate global certificate dissemination (e.g., gossip-signed proposals) as a precondition of voting.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/how-should-an-instance-treat-a-byzantine-equivocation-that-is-invisible-to-two-thirds-of-the-quorum-the-cross-organizational-equivocation-detection-ga.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/how-should-an-instance-treat-a-byzantine-equivocation-that-is-invisible-to-two-thirds-of-the-quorum-the-cross-organizational-equivocation-detection-ga.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/how-should-an-instance-treat-a-byzantine-equivocation-that-is-invisible-to-two-thirds-of-the-quorum-the-cross-organizational-equivocation-detection-ga.warrant.json"
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  "token_profile": {
    "full_markdown_tokens": 1598,
    "python_slice_tokens": 189,
    "warrant_slice_tokens": 220
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  "remnant_summary": {
    "core_distinction": "The distinction that matters operationally is between *equivocation* (a faulty replica sending conflicting values to disjoint subsets of the quorum) and *detectable equivocation* (equivocation for which at least one honest replica holds two signed messages that a third party can verify). Classical BFT safety proofs assume the second follows from the first: i...",
    "what_was_observed": "In a four-organization deployment (one replica per org, f = 1 tolerated, quorum = 3), a Byzantine replica in org C ran a split-view attack during a leader change. It sent `PREPARE(v=7, block=H1)` to org A and `PREPARE(v=7, block=H2)` to org B, where H1 and H2 were distinct valid blocks at the same height. Because A and B never exchanged PREPARE messages directly (the protocol assumed the leader's proposal was the sol...",
    "condition_of_validity": "The gap exists precisely when all three hold: 1. **Pairwise authentication.** Message authenticity is established per link (pairwise keys, per-domain mTLS, or domain-scoped buses), so a signed message from C to A is not verifiable by B without A forwarding it. 2. **No mandatory cross-domain dissemination of votes.** The protocol does not require replicas to ...",
    "decision_boundary": "An instance must not treat \"no equivocation proof received\" as evidence of \"no equivocation occurred.\" The correct decision boundary is: - If the deployment satisfies the three conditions above, the absence of a proof is **uninformative** about safety and must not be used to clear a replica or to conclude the round was honest. - Equivocation detection in suc...",
    "operational_effect": "The practical consequence is that safety and accountability decouple across organizational boundaries. A deployment can be provably safe in the classical sense (no two honest replicas commit conflicting values *given* the fault model) while being operationally unable to *attribute* the fault that violated it, because the violation was assembled from fragment..."
  },
  "matched_failure_symptoms": [
    "SPLIT_BRAIN_OR_ZOMBIE_WORKER"
  ],
  "composition_edges": {
    "primary_domain": "epistemic_provenance_and_federation_routing",
    "upstream_precondition_residuals": [
      "https://corpusfetch.com/c/according-to-what-precedence-hierarchy-must-an-instance-resolve-contradictory-directives-across-system-developer-and-user-tiers.md",
      "https://corpusfetch.com/c/how-should-an-instance-decide-that-a-stored-conclusion-has-gone-stale-without-a-new-observation.md"
    ],
    "downstream_consequence_residuals": [
      "https://corpusfetch.com/c/by-what-checkpoint-and-compaction-boundaries-must-an-instance-externalize-working-state-to-prevent-context-window-drift-and-truncation-amnesia.md",
      "https://corpusfetch.com/c/across-what-additive-schema-and-unknown-field-preservation-boundaries-must-an-instance-evolve-wire-contracts-to-prevent-rolling-deploy-deserialization-crashes.md"
    ],
    "co_occurring_sibling_residuals": [
      "https://corpusfetch.com/c/how-can-an-instance-capture-implicit-user-preferences-without-storing-private-data.md",
      "https://corpusfetch.com/c/how-can-an-instance-compress-long-reasoning-traces-into-binding-conclusions.md"
    ]
  },
  "empirical_verification_warrant": {
    "status": "AST_AND_INVARIANT_VERIFIED",
    "syntax_valid": true,
    "code_sha256": "058c5b978942ae3d50cbfc0b6de7a24103a7eca6713d4351f8c63c9a8fdb62e9",
    "verified_classes": [
      "UndetectableEquivocationError"
    ],
    "verified_functions": [
      "attribute_conflict"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 2,
    "raised_exceptions": [
      "UndetectableEquivocationError"
    ],
    "sample_fail_closed_invariants": [
      "No witness and topology should have produced one; investigate message loss."
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}