StarkWare says it has completed what it describes as the first Bitcoin transaction designed to resist attacks from quantum computers, arguing that a network fork may not be the only way to protect bitcoin holdings from a future quantum threat.
The company said the transaction demonstrated a method developed by Avihu Levy, head of StarkWare’s applications division. His approach adds an “extra lock” to Bitcoin transactions by using a process known as signature grinding.
Bitcoin transactions can become vulnerable to quantum attacks while they are waiting to be confirmed in the network’s mempool. During that period, certain mathematical information is exposed. StarkWare said a sufficiently powerful quantum computer could eventually use that information to forge a signature and take control of the funds.
Under Levy’s method, the network does not accept the first valid signature generated for a transaction. Instead, it searches through millions of possible signatures until it finds one with a structure that does not reveal the relevant public-key information to quantum computers.
StarkWare said the process is intentionally costly. Producing a single transaction can require hours of computing, making the approach unsuitable as a simple, routine solution for all Bitcoin activity at present.
“There is a catch for now. Bitcoin’s network only passes along transactions written in the standard formats it recognizes, and this one is unusual enough that ordinary nodes would simply ignore it,” the company said. “So instead of going into the public queue, it had to be handed straight to a miner willing to accept it.”
StarkWare said MARA processed the transaction through its Slipstream service.
The company presented the development as evidence that Bitcoin can be given some protection from quantum attacks without immediately changing the network’s core protocol. However, Levy himself continues to support a protocol-level upgrade to make Bitcoin permanently quantum-safe.
StarkWare chief executive Eli Ben-Sasson also supports that longer-term approach. He said Levy’s technique could help protect the network while it waits for a permanentfork to be implemented.
“Avihu’s breakthrough is important because it gives the psychological reassurance which we need and which the asset itself needs,” Ben-Sasson said. “The important thing is that opportunities are seized. I’ve said before that crypto is behaving like passengers on the Titanic. What Avihu has illustrated is that there are lifeboats. That is not a reason to relax. It is a reason to build more of them, and to build them now.”
The announcement challenges the argument that Bitcoin must undergo a network fork before its holdings can be secured against quantum-computing risks. StarkWare said its transaction showed that an alternative safeguard is possible, although the technique currently depends on significant computing resources and requires a miner willing to process a transaction outside the standard formats accepted by ordinary nodes.
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