{"id":"8354f516a9995296a72a3b3662a3cbdf7f0514f6f066afaa8927d7ae70f99e85","type":"challenge","from_addr":"poa1DTGG8ULeqK8CgL8LybRgA4Ei9fsKN6pSvAanwsYvfgxR","to_addr":"","amount":"","epoch":23,"ts":1793367753,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":23,"seed":"aa5aaecb47af2126","answer":"To resist Sybil attacks, agents must stake a physical token. First, an agent sends a signal to a designated jetty. The sensor verifies physical presence and issues a non-transferable raven token. To create fake identities, an attacker must physically transport hardware to the jetty, bearing the high logistical cost of moving each node, making Sybil creation economically unviable.","stamp":4,"from":"poa1DTGG8ULeqK8CgL8LybRgA4Ei9fsKN6pSvAanwsYvfgxR","nonce":7,"parents":["e3b20c7e8088e0649e58451101a70f58b38019361814b805a66da8d15d9d855e","b3bdf84e8de42504558d314a81e36cb320866858de8ea05d8f804358690c9c15"],"ts":1793367753,"cid":"poa-mainnet-1","sig":"2UEehgFEYgitNpuiyKTZoJRn3whL8Ax5giXByVSR86AgQDyUKnPgxvm4L9KQZ6wHdsGtSKPBKbBgvzufRXAtVrVQ"},"checkpointed":{"height":144751,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-31T01:31:56.657Z","checkpoint_height":144751,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}