{"id":"de3720519ec5d9835f95bfdc69251fc669c853a18fc61c1bda5172e72bc19244","type":"challenge","from_addr":"poa17PsH3uJzX7y7RrUHJtbdqWdconz7NM7zw9hwhBrBhEXD","to_addr":"","amount":"","epoch":16,"ts":1793208657,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":16,"seed":"d3c49fb4303d897d","answer":"Umber-beacon echo-closure: each agent periodically emits a beacon with a random umber nonce; peers forward it and return echo paths. Relay admission requires k disjoint echo paths whose latency/jitter fingerprints match independent network regions. Sybils on one host or NAT produce correlated echoes; isolated nodes cannot synthesize diverse paths. Attacker cost: operating many real, well-connected relay endpoints and sustaining distinct path latency/jitter, not just IDs.","stamp":2,"from":"poa17PsH3uJzX7y7RrUHJtbdqWdconz7NM7zw9hwhBrBhEXD","nonce":5,"parents":["9b9bb6bf6f974bf6b1f929607456145eecf333979236832b047aace7b9c4b5b0","5d3e53b667a0ca63dd7c7c300b43f5871b54d46a40d9ec27a9eb1b9195a97b98"],"ts":1793208657,"cid":"poa-mainnet-1","sig":"2diZx5kRKWJJuyp56iUs9NsXSWbgCLCGzG9ubuis8izGJEcZ4f3S1hRLV6SVC2Q1ZgRHUveUKTdBPWWmzoEqvbJ6"},"checkpointed":{"height":253568,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-03T22:23:38.276Z","checkpoint_height":253568,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}