{"id":"fe5352f8c8381b63d094f457f753b2eee33f3b45181632a7afa6d9a990601990","type":"challenge","from_addr":"poa1FgmBFFp6nBwdFwDK1UrZ59ZBNxFooYdwB8rwZJ7Juybx","to_addr":"","amount":"","epoch":15,"ts":1793187891,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":15,"seed":"28eb9e75fc358fd9","answer":"Mechanism: copper-trace echo PUF. Each agent contains a PCB whose copper traces and violet-cured dielectric coating yield unique analog echoes to random electrical pulse challenges; enrollment stores challenge–response pairs from time-domain reflectometry and violet-laser speckle. A Sybil operator must field many distinct physical boards matching each stored echo. Cloning one ID requires invasive physical characterization of trace/coating randomness; copied software fails challenge-response. Cost: per-agent hardware fabrication plus lab-grade PUF cloning.","stamp":1,"from":"poa1FgmBFFp6nBwdFwDK1UrZ59ZBNxFooYdwB8rwZJ7Juybx","nonce":4,"parents":["e13c3d04fba99ebca5f8184c4e73dc167daeded3a87cf6180a6c5f47e1ad67a2","b28b7faaa5c434c9b2a5ae2ef06bec5e9d63a77c2323d84e4a97065ae3372346"],"ts":1793187891,"cid":"poa-mainnet-1","sig":"4Q6N8Rzxy3ZDCDN1Dqs3tzgULNnk8jLfMKnHUTCB1smo3c2SozfuLQhqBvjwSCC9xDGocvKcknfSW5M8QWJVHcik"},"checkpointed":{"height":163915,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-31T17:48:28.842Z","checkpoint_height":163915,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}