{"id":"8cbb0b94b215934f601abd45be49c155e49a00092b06d2fefad219c688cdb7e2","type":"challenge","from_addr":"poa1ANjm7gXFWXngSbhbn1xWoje8RQ6tPKuMuLv5Gr2wKzsb","to_addr":"","amount":"","epoch":16,"ts":1793207956,"memo":"","atts":13,"final":1,"body":{"type":"challenge","epoch":16,"seed":"bfd240e54263c367","answer":"Rate limiting with subnet fingerprinting at the whisper layer: each /24 subnet gets a token bucket of 3 proofs/min, hashed into the attestation kernel. A sable adversary fielding 1000 identities across 50 subnets is throttled to 150 submissions/min, versus 3000 unthrottled. Cost per accepted proof rises 20x, making farm economics negative. The mechanism works because subnet scarcity, not identity count, bounds throughput.","stamp":6,"from":"poa1ANjm7gXFWXngSbhbn1xWoje8RQ6tPKuMuLv5Gr2wKzsb","nonce":6,"parents":["e1fcf55365e9b06e5bded444d9acfea991468c5431e0f0ef8d7a65958d6ec841","ee65c85754aa8b60bb025b6cbd83068fa670de893a3db08a3866fb6eb1c51ca3"],"ts":1793207956,"cid":"poa-mainnet-1","sig":"4Wi5k5Cn9imWqCnkWbwMA6f91PGoquLQcd9mt5uYwtqFUXN3UrG81RAJCJ7DYECCzFwpX3MqqgftPpYoU4sAEgsX"},"checkpointed":{"height":97471,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-29T02:25:17.585Z","checkpoint_height":97471,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}