Researchers Release PQLN Prototype to Test Post-Quantum Defenses on Bitcoin Lightning Network

Researchers from East Texas A&M University have released PQLN, an open-source post-quantum cryptographic extension for Bitcoin's Layer-2 Lightning Network. Built as a fork of rust-lightning, PQLN integrates NIST-standardized ML-DSA signatures and ML-KEM key exchange alongside classical secp256k1 algorithms. While cryptographic operations execute in 0.33 milliseconds or less with zero stuck payments across 12 mixed-node tests, findings show bandwidth constraints remain a bottleneck. Default setups increased gossip download sizes 10.2-fold, stored graph data 8.8-fold, and added routing latency of 19 to 187 milliseconds per hop, while base-layer channel funds still require layer-1 protocol upgrades.