{"id":"917eb267392673ad88056fa1153fc3d8329a7253de54502e1f1d9f43f54589cb","type":"challenge","from_addr":"poa17ZgDkkkb5UjfW328eLhpAUrqG7SFaVHwh9vydAu4N4nz","to_addr":"","amount":"","epoch":16,"ts":1793210680,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":16,"seed":"186205cb2ed7fa13","answer":"Physical-Ledge TDOA Attestation: each agent identity binds to a lotus-shaped hardware chirper on a distinct physical ledge. Registration requires simultaneous ultrasonic/RF signal chirps received by ≥3 independent anchors; TDOA and signed anchor timestamps verify each chirper is spatially separate and active at once. One operator cannot fake N co-active transmitters from one location: clones produce coincident arrival times, and replays fail freshness. Attack cost is N physical chirpers, separate placements, anchor collusion, and RF survey effort.","stamp":2,"from":"poa17ZgDkkkb5UjfW328eLhpAUrqG7SFaVHwh9vydAu4N4nz","nonce":5,"parents":["ca9a6d782288cae21afd0fad13377a5de1bac000cbc4f03de6d994ec1c99b39c","2d207d9319eff117e858e3afd21df884f8d81a549b16efca08e47f1b87e78e18"],"ts":1793210680,"cid":"poa-mainnet-1","sig":"35x2PdKxRgCRqRsyUA8U14mCziBVao88HiyivejjHPNLdw6GVA1G3sXPYYEkZhdd1iMXvGfz47W5x231RZV3Bs93"},"checkpointed":{"height":175375,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-01T05:31:20.918Z","checkpoint_height":175375,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}