Researchers from East Texas A&M University, North American University, Florida Gulf Coast University and Florida Institute of Technology announced the design on Tuesday. The researchers said the design is the first full post-quantum security design for the Lightning Network. The team said the implementation adds post-quantum cryptography to Lightning's communications, payment requests and related systems in Rust-Lightning. The work was first disclosed in a research paper in September.
The solution layers quantum-resistant cryptography over Lightning's existing cryptography rather than replacing the existing cryptography. The design uses ML-DSA digital signatures and ML-KEM key exchange alongside Lightning's classical cryptographic methods. The U.S. National Institute of Standards and Technology standardized the post-quantum algorithms. An attacker would have to break both the new and existing cryptography to compromise a connection or forge a payment request.
Dr. Ahmet Kurt leads the research team and is an assistant professor in East Texas A&M's Department of Computer Science and Information Systems. The team said the implementation took about three to four months and roughly 11,000 lines of code. The team said the implementation is complete and working, rather than a small demonstration.
Lightning enables fast, cheap Bitcoin payments through off-chain channels instead of recording every payment on the blockchain. The team said powerful quantum computers could eventually break Lightning's cryptography. The team said that risk remains even if Bitcoin itself receives an upgrade because Lightning has separate communication and payment systems. The researchers said the work demonstrates that Lightning's off-chain systems can begin preparing independently while others focus on quantum defenses for Bitcoin's mainnet.
Quantum researchers have warned that Bitcoin's software will eventually need an upgrade to address quantum computing. Some cryptocurrency venture capital firms have urged action. However, top developers have argued that many current quantum computers have limited capabilities. Those developers have also noted that quantum advances could arrive unexpectedly, as advances in artificial intelligence have. Developers, including Bitcoin infrastructure firm Blockstream, have begun developing solutions.