Google announced an ambitious timeline to migrate most of its authentication and digital signature frameworks to post-quantum cryptography by 2029. This accelerated schedule reflects rapid improvements in quantum hardware performance, error correction techniques, and reduced resource estimates for breaking current cryptographic algorithms.

Two primary threats drive the push: 'store-now-decrypt-later' attacks that capture encrypted data today for future decryption, and direct assaults on digital signatures that authenticate transactions. For blockchain networks, signature forgeries could allow attackers to drain wallets and hijack assets.

Chaincode Labs estimates about 50% of Bitcoin—roughly $700 billion—is vulnerable to quantum attacks, while the Ethereum Foundation has outlined a four-pronged roadmap targeting post-quantum protections by 2029. Bitcoin developers have proposed BIP360 to integrate quantum-resistant signatures, emphasizing proactive preparations over reactive fixes.