Researchers at the East Texas A&M University RELLIS Campus introduced PQLN, a post-quantum security layer for the Bitcoin Lightning Network. The project, published on September 12, 2026, includes nearly 11,000 lines of code added to a fork of rust-lightning and is available on GitHub.
PQLN integrates lattice-based algorithms, specifically ML-DSA for digital signatures and ML-KEM for key exchange, onto the existing infrastructure. These tools align with standards from the US National Institute of Standards and Technology to protect communication and routing layers.
The system covers five operational areas: gossip, peer transport, invoices, payment onions, and offers. Benchmarks show that added cryptographic operations take 0.33 milliseconds or less. While default settings increase gossip bandwidth by 10x, using the Falcon scheme reduces this to 4x.
The design ensures backward compatibility, allowing upgraded nodes to communicate with legacy ones. Interoperability tests across 12 mixed-node configurations resulted in zero stuck payments. However, PQLN does not secure on-chain Bitcoin funds or channel balances, as those require a consensus upgrade.
