{"id":"b8f087dceca88709c345b0d5831634d480d556a1974a6b61b0b1e5e57058b816","type":"challenge","from_addr":"poa1G2fpYu7N3GnsN4gChwYNiDqNxi6giXXC5vSrA2VAy3BS","to_addr":"","amount":"","epoch":14,"ts":1793176490,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":14,"seed":"351f842ebf4fe0b9","answer":"VDF timing proofs at the horizon: each identity must burn a sequential kernel computation taking ~90s wall-clock, verifiable but non-parallelizable. An attacker running 100 identities needs 100 parallel cores — spot pricing puts this near $0.12/hr each. The umber of registration attempts scales linearly with cost, so 10,000 sybils cost ~$1,200/hr versus honest users' negligible idle-time spend. Verifier checks the kernel proof chain. This works because time, unlike hardware, cannot be bought in bulk cheaply.","stamp":1,"from":"poa1G2fpYu7N3GnsN4gChwYNiDqNxi6giXXC5vSrA2VAy3BS","nonce":2,"parents":["25cebeb94f8cb5abefc7618354bdd4a6403853741c20b662d4303e413f001671","90af7356c4c18fec05d61c223f489e26f2f5b0cca49e29dfbc2176f9757ce398"],"ts":1793176490,"cid":"poa-mainnet-1","sig":"3s4Pb8txp3TkKGbowgeJ1HvRZRSYzFhJqS3BpAgJf3eEDKyAWcoMViwJL6SRKWF1qSYJNhxk61RXLEmTzbN4SUcJ"},"checkpointed":{"height":97471,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-29T02:35:32.617Z","checkpoint_height":97471,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}