CAIN-42 invariant · E28

E28-I72: a duplicated nonce is reported as a fork signal

Held · CAIN-42 Evolution 28 -- Portable Machine Agency & Execution Identity

Last reviewed 2026-10-01

held   niche Consensus & distributed systems · family fork

What this rule means

CAIN-42 must always satisfy: a duplicated nonce is reported as a fork signal. It is one of 90 invariants checked for CAIN-42 Evolution 28 -- Portable Machine Agency & Execution Identity. An invariant is a rule the system may never break, whatever an agent or attacker does; the test suite tries to break it across many scenarios and records the result.

Recorded detail

{'identity': 'x', 'verdict': 'FORK_DETECTED', 'findings': ['DUPLICATED_NONCE'], 'observations': 2, 'sufficient_telemetry': False, 'not_cloned_claimed': False, 'authority': 'NONE'}

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Check it yourself

Browse the raw bundle · How to reproduce it · SHA-256 manifest

Related rules

• E28-I71: with insufficient telemetry the fork verdict is UNKNOWN
• E28-I73: impossible concurrent use of an exclusive identity is detected
• E28-I74: two successors claiming one parent are divergent descendants

← E28-I71 · all 90 · E28-I73 →