Google: The quantum resources required to break elliptic curve cryptography are significantly lower than expected. It is recommended that blockchain complete post-quantum cryptography migration before 2029.

Deep Tide TechFlow message. On March 31, Google’s Quantum AI team released a white paper, stating that the number of qubits and the number of gate operations required by future cryptography-related quantum computers (CRQC) would be lower than previously expected—meaning they could break the elliptic curve cryptography (ECC) currently widely used for encrypting cryptocurrencies.

The white paper shows that the research team compiled two quantum circuits targeting the 256-bit elliptic-curve discrete logarithm problem (ECDLP-256): one uses fewer than 1,200 logical qubits and 90 million Toffoli gates; the other uses fewer than 1,450 logical qubits and 70 million Toffoli gates. It is estimated that the above circuits can perform the computations within minutes on superconducting quantum computers with fewer than 500,000 physical qubits, which reduces the required number of physical qubits by about 20 times compared with earlier estimates. Google previously published a migration timeline for 2029, advising the cryptocurrency community to migrate blockchains to post-quantum cryptography (PQC) before that deadline, and calling on people to avoid exposing or reusing wallet addresses that have vulnerabilities.