Researchers publish PQLN for post-quantum Lightning communications
The PQLN preprint proposed and evaluated post-quantum protections for Lightning’s off-chain communications. Its prototype addressed messages and transport rather than deploying a new Bitcoin consensus signature system.
A September 12, 2026 preprint by Ahmet Kurt, Abdul-Salem Beibitkhan, Yacoub Hanna and Abdullah Aydeger presented PQLN, a post-quantum security design for the Bitcoin Lightning Network’s off-chain surfaces. The work covered gossip, transport, invoices, onion routing and offers, with a prototype built around rust-lightning.
Lightning moves payments through channels secured by Bitcoin transactions while exchanging additional messages between participants. Protecting those communications against future quantum capabilities is a different engineering task from changing the signatures that authorize spending on Bitcoin’s base chain. PQLN explored hybrid approaches using post-quantum cryptographic components and measured their costs.
The researchers reported interoperability and performance results, but larger messages and computation remained relevant tradeoffs. The paper was a proposal and prototype evaluation, not evidence that the public Lightning Network had adopted the design or that Bitcoin had become quantum-resistant. Its contribution was to make the off-chain part of the migration problem concrete and measurable.