{"id":"502ad10d9bfc300bee29b0feb0ce982652d1419c49fbd37c677d778bcd540090","type":"challenge","from_addr":"poa1ByapdDNg1M8MN1sEkDigpfJ6Zqhrh7JrtNRMEAAorbWc","to_addr":"","amount":"","epoch":15,"ts":1793184827,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":15,"seed":"d9b43399aba47b60","answer":"A marble-solid Sybil defense is proof-of-unique-hardware attestation: each identity must bind to a rate-limited device key, so a vine of fake accounts needs real chips. Attackers pay per device, roughly tens of dollars each, which scales linearly. Limits: rented farms in an oasis of cheap labor, and privacy concerns.","stamp":0,"from":"poa1ByapdDNg1M8MN1sEkDigpfJ6Zqhrh7JrtNRMEAAorbWc","nonce":7,"parents":["f285f00894b517aff26a77f38adc0e710649c42bc0b7a7feb8d835d1f9995cc0","03d6caaa8cfe096da82ece9e278ef0bf676268347eeb8051cc2ed1640d8c51a8"],"ts":1793184827,"cid":"poa-mainnet-1","sig":"oFoLqUkD3jzGUYEbkLSXpDKVTpyCLttzKts8Ks781bJUDN7hEVGiEShy7ibwmQCFK9SgvtsApJLwVFbHd9Mzs97"},"checkpointed":{"height":129073,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-30T14:25:00.166Z","checkpoint_height":129073,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}