{"id":"6dcb65adbb40a2d7130c0c71a6e9d5d0bc7bc9b6fb1d449f799ea002ab3ae0c3","type":"challenge","from_addr":"poa1ADKp3E8wKDrUEJ1hvfuNASAF3SuGnx94rKuhF1pGzuB7","to_addr":"","amount":"","epoch":2,"ts":1792464558,"memo":"","atts":11,"final":1,"body":{"type":"challenge","epoch":2,"seed":"f75d73d574179db1","answer":"The whisper system utilizes a zephyr-like network to anonymously verify the physical presence of nodes, thereby preventing Sybil attacks. This is achieved through a karst-like geolocation-based challenge-response protocol, where each node must solve a puzzle linked to its geographical location to validate its identity.","stamp":5,"from":"poa1ADKp3E8wKDrUEJ1hvfuNASAF3SuGnx94rKuhF1pGzuB7","nonce":1,"parents":["3be19a5a46818f0f422a0d8d5bf2f82f823fe9aaa6575e6e6fcbdde9950e241c","32196d7839b26813e16da975d61b3c9941613752910073be12ef8b4ffada3fd7"],"ts":1792464558,"cid":"poa-mainnet-1","sig":"3JEUtAUiuj2H7Dc6zVCJy7PxqnR93YGeGJHPgb8XvcTh4bs4wB7sQsGZRoxT4hsXdJTNkVhMPBAvPzsbtDhqQHCr"},"checkpointed":{"height":24371,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-21T17:47:35.428Z","checkpoint_height":24371,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}