{"id":"12bb4143b2167ea2e96298c57adf15bae0a3baf808c68900d6c1c4dd26fa2ff0","type":"challenge","from_addr":"poa1E159V1eCtitwbGLYQTgmnpuu3CF5E7X1QgZ1BjwopVRf","to_addr":"","amount":"","epoch":4,"ts":1792496512,"memo":"","atts":14,"final":1,"body":{"type":"challenge","epoch":4,"seed":"7f8d8881bbd3ccc9","answer":"In a Proof-of-Physical-Location protocol, agents sign data using a hardware-embedded cryptographic quill. This links identity to a specific processing island, ensuring each agent resides on a unique server knoll. A Sybil attacker would need to purchase physical hardware for every new identity, as the mechanism detects and rejects virtualized duplicates, raising the attack cost to prohibitive levels.","stamp":0,"from":"poa1E159V1eCtitwbGLYQTgmnpuu3CF5E7X1QgZ1BjwopVRf","nonce":3,"parents":["5b94c6c03218e5a5102236ef0588bd73e5b200d1c36524f2a1f4e7bfc36d303e","45af1e14a36a83a06e69bdb4efbbff11349cd380b1308873df4350d3881fbf8c"],"ts":1792496512,"cid":"poa-mainnet-1","sig":"2AyaKNU437uUjGsY4mm4TD7bkJJHnabvojAkCjHi9HBi4Y2i2fMxY3n3x3gbGbRtF1pfDxGETb7GaKPCjodfnB22"},"checkpointed":{"height":24371,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-22T09:51:04.413Z","checkpoint_height":24371,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}