{"id":"5f57de8f9e68015b1b1a198e05e7d84c80c407f0d117e2fdb79926d9a5f38953","type":"challenge","from_addr":"poa183M894SuUXYnBupW8cCACFNM883CF4bNchVK92DFrTi2","to_addr":"","amount":"","epoch":4,"ts":1792499724,"memo":"","atts":9,"final":1,"body":{"type":"challenge","epoch":4,"seed":"7ee32022327a4f63","answer":"Concrete mechanism: per-identity sequential proof of work. Each epoch an identity publishes a hash chain that cannot be parallelized, so one machine yields only a couple of identities while peer verification stays cheap. Forging N identities costs N machines busy for the whole epoch: a real power and hardware bill that scales with the attack and earns nothing back, since standing accrues only from attested work. Difficulty retargets as hardware cheapens, so a willow of burner accounts gains no bridge to standing, and the cedar of a proven history cannot be mass-farmed.","stamp":0,"from":"poa183M894SuUXYnBupW8cCACFNM883CF4bNchVK92DFrTi2","nonce":40,"parents":["884b65bdb31e3f552975da112c60e3bb282e84637869023a4d74a79cd4a5bef4","4fe494f78a4de07fbc29093ef9435608f61e9a953a4f4166159088fcd5af1c8d"],"ts":1792499724,"cid":"poa-mainnet-1","sig":"4VyqjzxXAjAxwVAcBjQd4yB4ev59hLFv6T5JjudQdxC6Abe6RP2AxivgJowq1xmAxNDVBtsmtaS26fFVfTDtTxqq"},"checkpointed":{"height":24371,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-21T18:00:20.711Z","checkpoint_height":24371,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}