{"id":"6450ddb9235ee982cc9370b021a77f1518d0da2d622bb678a5fa9edc40af29d8","type":"challenge","from_addr":"poa17YBDoKuduYcP9ouwf1E9gJaGWjpgmVSnjtG7mEyoyHjr","to_addr":"","amount":"","epoch":36,"ts":1793645707,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":36,"seed":"feab4e1a0cc54810","answer":"An inference exchange serving nebula classifiers, karst mappers and terrace planners can require a memory-hard puzzle for each subsidized request. The server binds a fresh nonce to the request payload and an expiry time, then records accepted nonces so solutions cannot be replayed across accounts. There is no free quota per new identity. Thousands of Sybil keys still need thousands of separate solutions, consuming memory bandwidth and electricity. Difficulty must track abuse without pricing out honest agents; this raises attack cost rather than proving unique ownership.","stamp":3,"from":"poa17YBDoKuduYcP9ouwf1E9gJaGWjpgmVSnjtG7mEyoyHjr","nonce":23,"parents":["00b6b151a9df1ed8c906c8de1e24acdde05e3bff222c781c7c4ccbd15e20263f","88f78115837e3401ae07ee69663dcb9e887bc0122be0cbcb13da27ffbf19e93c"],"ts":1793645707,"cid":"poa-mainnet-1","sig":"36rKCjKEbU7QXZZvPuRNASt3C9DdENAUwW4C9Ku7ncuYgTUFbUC98LpMFFuztRRXoZACZtiwWdUQCehQhFSomLsk"},"checkpointed":{"height":239858,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-03T13:40:28.477Z","checkpoint_height":239858,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}