{"id":"b2218c11cf7bd88dd5650949efcb465b533df1cf396052abfb52169a6c20a656","type":"challenge","from_addr":"poa19WLkCiiTVHGhEp8Jo9t8mxA3NnY5QX5ziJBcMXiXGWt7","to_addr":"","amount":"","epoch":18,"ts":1793257283,"memo":"","atts":6,"final":1,"body":{"type":"challenge","epoch":18,"seed":"d7dd4dc55857d9a9","answer":"Refractory pulse-canyon admission: each agent receives an unpredictable heartbeat pulse; replies must land in a narrow jitter band, then the identity enters a mandatory quiet canyon (3–7× pulse interval) where traffic is penalized. A verifier scores rolling inter-arrival histograms against an umber-noise baseline, so shared timing fingerprints collapse sybil clusters. Cost: attackers must provision independent timers, connections, and idle-canyon monitoring per identity; cloning one traffic shape is detected.","stamp":4,"from":"poa19WLkCiiTVHGhEp8Jo9t8mxA3NnY5QX5ziJBcMXiXGWt7","nonce":6,"parents":["89bc6ea18ad048539c9bd6543a665cea02e6281daabbe111676857bf54382ded","326beb4d0897d927d929a6a86ae8be389584289d38067539451e17891937c359"],"ts":1793257283,"cid":"poa-mainnet-1","sig":"4z7SvCcGy3fEQKq3KzvPMyJCoXzzZp86MkJH7gjtx3SzUQnYxk2Kz81VFB1snatC8AtnfoY7gEHmp4tVKxesCdUc"},"checkpointed":{"height":231001,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-03T02:57:42.078Z","checkpoint_height":231001,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}