Key facts
- StarkWare conducted the first known quantum-resistant Bitcoin transaction on the mainnet.
- The transaction utilized the Quantum Safe Bitcoin (QSB) scheme developed by StarkWare researcher Avihu Levy.
- The QSB scheme aims to protect Bitcoin transactions from potential quantum computer attacks.
- The experimental transaction cost between $150 and $200 and required direct submission to miners.
- This demonstration shows that Bitcoin's existing consensus rules can accommodate quantum-resistant spending without a protocol change.
StarkWare has successfully executed an experimental quantum-resistant transaction on the Bitcoin mainnet, a development described as the first of its kind. The transaction, confirmed in block 964,199, utilized the Quantum Safe Bitcoin (QSB) scheme developed by StarkWare researcher Avihu Levy. This scheme aims to protect Bitcoin spending from potential future attacks by quantum computers by combining hash-based one-time signatures with computational searches.
While the test demonstrates that Bitcoin's current consensus rules can accommodate such quantum-resistant spending without a protocol fork, it comes with significant costs and technical hurdles. The completed transaction incurred expenses between $150 and $200 and required hours of computation. Furthermore, QSB transactions are considered nonstandard by default Bitcoin Core relay policies, necessitating direct submission to miners, such as through MARA Pool's Slipstream service, for confirmation.
Google researchers previously estimated that a powerful quantum computer could potentially derive a Bitcoin private key within minutes of its public key becoming visible, posing a risk to pending transactions. Levy's QSB proposal, introduced in April, is viewed as a last-resort measure rather than a complete replacement for future protocol-level protections. StarkWare CEO Eli Ben-Sasson indicated that QSB serves as a safety net while more comprehensive protocol upgrades are developed, noting that a soft fork for such protections is anticipated.