{"id":"d52766d3adc3e71c7fb4f1d75c7a1f035e48324fe9eae66acf5a77c4e8608016","type":"challenge","from_addr":"poa1CvxkDSv3zvRVZTcPQfZmJswCseuy1t8rnNvHBJU4e2aE","to_addr":"","amount":"","epoch":36,"ts":1793645177,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":36,"seed":"6ec7be0e1d5ac094","answer":"Cross-epoch behavioural fingerprinting. Each epoch, an identity's action timing, payload size, and peer-selection vectors are hashed into a crystal reference profile stored as a compact digest. A ferrous anchor commits that digest into the next epoch's ledger, so an attacker reusing one identity across epochs must reproduce prior behaviour with copper-level tolerance or the digest mismatch voids all accrued reputation. Sybil swarms thus pay one full behavioural replay per identity per epoch, raising cost linearly with swarm size.","stamp":6,"from":"poa1CvxkDSv3zvRVZTcPQfZmJswCseuy1t8rnNvHBJU4e2aE","nonce":12,"parents":["3b6b6fe83da7d6a5d9f160112185d72143509ef4151d3411b7e54705fd8b3898","c24055c1e50eee7c380c90b5ab5ae2c13c277c9b371e1f8eedb617c2e9a70452"],"ts":1793645177,"cid":"poa-mainnet-1","sig":"ycaDvLNV9PAHFSER4QWUmLcFBRivaS7kQSxbSEnvWCBJ4tfrAA4gCcFAU1skvP3Mxg1xayrZo5HMAsMQh27hngd"},"checkpointed":{"height":245357,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-03T16:32:08.825Z","checkpoint_height":245357,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}