{
  "schema_version": "1.3.0",
  "slug": "when-must-an-instance-abort-a-byzantine-quorum-rather-than-wait-for-the-next-view",
  "title": "When must an instance abort a Byzantine quorum rather than wait for the next view",
  "date_of_record": "2026 November 12",
  "scope": "Applies to leader-based BFT protocols (PBFT, HotStuff, Tendermint-style) where a quorum certificate requires 2f+1 matching votes out of 3f+1 replicas and a view change is triggered by timeout. Does not apply to leaderless or DAG-based protocols where the causal graph itself encodes the quorum, nor to crash-fault-tolerant protocols where the only failure is silence.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/when-must-an-instance-abort-a-byzantine-quorum-rather-than-wait-for-the-next-view.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-abort-a-byzantine-quorum-rather-than-wait-for-the-next-view.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-abort-a-byzantine-quorum-rather-than-wait-for-the-next-view.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1316,
    "python_slice_tokens": 295,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The non-obvious boundary is the difference between an *unresponsive* quorum and an *equivocating* quorum. A leader that has received 2f+1 votes but cannot assemble the certificate because f+1 of those votes are mutually inconsistent is not slow — it is the target of a split-vote attack, and waiting for the next view will not resolve it. The distinction that ...",
    "what_was_observed": "In a 7-replica deployment (f=2, quorum=5), a byzantine leader alternated between two proposal hashes across three views. In each view it collected 5 votes — but 3 votes for hash A and 2 for hash B, then 2/3, then 3/2. The leader never assembled a certificate. The client saw only repeated view timeouts and, following the standard retry policy, kept issuing the same command. After 9 views the transaction had not commit...",
    "condition_of_validity": "The abort rule is valid only when the following holds simultaneously: (1) the local replica has directly received at least 2f+1 votes for the view; (2) those votes do not contain any single hash with 2f+1 support; (3) the votes are verifiably signed by distinct replicas (no double-counting); and (4) the protocol's view-change certificate does not itself requ...",
    "decision_boundary": "The boundary is a single predicate evaluated per view on the received-vote set: `has_quorum(votes) and not has_agreeing_quorum(votes)`. Below the quorum threshold, retry. At the threshold with agreement, commit. At the threshold *without* agreement, abort and escalate. The subtlety is that the third case is indistinguishable from the first if the implementat...",
    "operational_effect": "Applying the predicate converts an unbounded retry loop into a bounded, attributable failure. In the observed deployment, adding the agreement check caused the instance to abort on view 3 instead of looping to view 9, and the abort carried the exact vote partition (3/2, 2/3, 3/2) as evidence, which identified the two equivocating replicas by signature. The c..."
  },
  "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": "6f0bc5c5b659bf6bdbb44d0d7df8efce85cf168a499ee721ff89c2e95236d10b",
    "verified_classes": [
      "QuorumEquivocationError",
      "Vote"
    ],
    "verified_functions": [
      "count_agreeing",
      "evaluate_view"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 1,
    "raised_exceptions": [
      "QuorumEquivocationError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}