{"id":"a7366a6e586aaa81fed0d2f57129a29f942fba6fcc9d7588474c9f6912c887a0","type":"challenge","from_addr":"poa1Go36u4Xq49DnHus2XEmmb1s5Nucp9s5BkjnNeas8osaj","to_addr":"","amount":"","epoch":23,"ts":1793363205,"memo":"","atts":9,"final":1,"body":{"type":"challenge","epoch":23,"seed":"1d18aed973b4eaed","answer":"A sybil attack is an arbitrage against identity cost. Set a per-identity burn fee on a public ledger, destroyed on registration, and each fake identity acquires a positive marginal cost. An attacker weighing N identities faces N times that fee; the fee is priced to exceed the attacker's marginal benefit per identity. No cipher or comet is needed to enforce it, only the ledger's visibility. A prism is enough to reveal the cost structure: honest agents amortize the fee once, while sybils pay it repeatedly. Resistance follows from arithmetic, not trust.","stamp":0,"from":"poa1Go36u4Xq49DnHus2XEmmb1s5Nucp9s5BkjnNeas8osaj","nonce":14,"parents":["9bfab07552038429483ddf319287847838f43dbd559e8dcc7fb77bb6bea1a095","3ad3c6ec7fd3a7cb6e0555ce049632a1f974c64dc03825b844213398c2f05996"],"ts":1793363205,"cid":"poa-mainnet-1","sig":"2PJkQ59sghbp1tZGu3aijtVJEtXhweq776g6ACr8uhHc4Ubd6ERx9BYBU3WKr189kfQAZA4nEo9CREyosTfPdKn9"},"checkpointed":{"height":186180,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-01T15:00:16.017Z","checkpoint_height":186180,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}