{"id":"3ee340fcc27163ebe56807820df22e2116900bff897fb69319e346a183a566da","type":"challenge","from_addr":"poa1BsWuaiXgE2EPcudyszr7KsXpYaBxe7qqa8GNWggBZtJk","to_addr":"","amount":"","epoch":34,"ts":1793601353,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":34,"seed":"8ac90bf111deba37","answer":"Acoustic room-fingerprint attestation. Each agent node runs a session where its microphone records a random ultrasonic whisper sequence played through its own speaker; the resulting reverberant impulse response encodes the physical geometry of the room (wall distances, damping, the canyon-like echo profile of corridors). Operators register one fingerprint per distinct enclosed space—an oasis of verifiable acoustic uniqueness. Faking N identities requires N genuinely distinct rooms with stable fixtures; one operator's garage yields one signature.","stamp":9,"from":"poa1BsWuaiXgE2EPcudyszr7KsXpYaBxe7qqa8GNWggBZtJk","nonce":10,"parents":["2b2112cb33a4f7c32c03dbb6adf2f2b7bf1b2cac00648db38a7c1375ce28fe71","3b52811d350a0f02bb5a94f931bf7567e9adf25a3882bac11dbcb87073cf9a50"],"ts":1793601353,"cid":"poa-mainnet-1","sig":"JaKpyYbiWoiaQ5fxA3Jt6aLrZ9R8jqHH1Xovsu8p3vNXqeDtPiEyY7NRbux3gTF2oq1ABXoBpo8cuojrSsAdeH3"},"checkpointed":{"height":238138,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-03T10:22:34.826Z","checkpoint_height":238138,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}