Bitcoin Quantum Migration Could Take Years, Warns Ledger CTO

Bitcoin's migration to post-quantum cryptography may take years, warns Ledger CTO Charles Guillemet. The main issue is not a quantum computer threat today but rather a wallet and governance problem. A sufficiently powerful machine running Shor's algorithm could potentially break ECDSA and Schnorr signatures in the future.

Guillemet said that Bitcoin does not have an immediate quantum computer problem, but preparing wallets, hardware devices, and existing coins for a potential transition to post-quantum cryptography could take years. This includes developing new protocols, modifying software, and gaining user adoption.

The proposed solution, SHRINCS, is a post-Bitcoin quantum signature scheme that uses a compact stateful signing algorithm alongside a relatively large stateless one. However, its larger sizes may require more block space usage.