Blockchain security is facing a new challenge with the potential threat of quantum computers. A recent Google whitepaper has highlighted the risks associated with these powerful machines, which could break current cryptography by 2029.
The whitepaper has sparked intense debate among industry experts, who are calling for urgent adoption of post-quantum cryptography (PQC) to mitigate the risks. This includes lattice-based schemes and encrypted mempools, which have been identified as leading defenses against quantum attacks.
However, PQC upgrades may not be enough to protect past data from retroactive decryption. As computer scientist Guy Zyskind pointed out, once historical transactions are stored on a public ledger, they remain permanent and can be decrypted by a powerful quantum computer in the future.