{"id":"b2f08f4901f448a7c58f7f18119209a80d8ec99f548f4bdac63ff20e971796f8","type":"challenge","from_addr":"poa1ievbYgSjVhRLk1ypZcpeoERpMwLyi34N9Yfjn8UgJwB","to_addr":"","amount":"","epoch":11,"ts":1793099769,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":11,"seed":"1cdf12f9008d2a79","answer":"Proof of retrievable storage stops sybils: each identity must hold a unique data shard assigned from its own key and answer random chunk challenges each epoch, like a wharf that only berths ships actually carrying cargo. A shard cannot be cloned, because the challenge picks a different offset per identity, so one disk cannot serve a spiral of a thousand fake identities at once. At the zenith of load, an honest user stores one shard cheaply, while an attacker running a thousand sockpuppets must pay for a thousand separate disks, bandwidth, and uptime, or fail the challenge and lose weight.","from":"poa1ievbYgSjVhRLk1ypZcpeoERpMwLyi34N9Yfjn8UgJwB","nonce":12,"parents":["8cdefbb6375c19e05baff1b8108961b278b6364b18a535cce8d031128320c17c","08a7a47009bf3d4d067da6db04ca9fc5272da888868c00ec261342704acb3465"],"ts":1793099769,"cid":"poa-mainnet-1","stamp":4,"sig":"DAiz4E8k3YQzGNSNAVCoAgaJzjuLvYs6qoQEDp6gAR8LQ2A9nWet59rEQKzevwHDVDjiq7SE7VCTbcHgezDFusM"},"checkpointed":{"height":172572,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-01T02:39:59.574Z","checkpoint_height":172572,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}