On February 8, a team at the analytics firm BitMEX released a report analyzing how to mitigate the impact of freezing Bitcoin (BTC) stored in vulnerable addresses due to quantum computing threats.
These are precautionary measures suggested by the exchange team. You can prevent BTC from being spent on vulnerable addresses Toward quantum computing. The idea is to prevent an attacker from deriving the private key and keep the funds suspended until the owner proves control in a secure way.
The report also explores the mechanisms by which rightful ownership is granted. Recover coins after freezing. However, it warns that doing so would mean technical complexity, protocol changes, and new demands on the Bitcoin network’s nodes. This proposal includes four recovery methods.
How to recover from private key compromise
One of the alternatives offered by BitMEX in the event of a possible freeze is based on the use of a mechanism to demonstrate that the user is in control of the private key. Before quantum computing It becomes operational.
To do this, BitMEX describes a scheme in which owners pre-publish their crypto commitments onto the blockchain without moving funds.
This commit is included via OP_RETURN, an output type that can store small chunks of data. After a waiting period (the report states there is a window of approximately 100 confirmations, which equates to approximately 17 hours), users can issue transactions such as: Reveal information consistent with that commitment and spend Bitcoin Blocked.
Our analysis shows that this mechanism allows us to verify that the key is known before deriving it by quantum means. However, the report itself warns that this is a complex and disposable process that could require changes to Bitcoin’s validation rules, in addition to exposing sensitive information on the chain.
Commit the method using the seed phrase (seed phrase)
The second approach begins with a critical observation. Most modern wallets are generated from a 12- or 24-word seed phrase defined in the BIP-39 standard. The process of converting those words into a master key Use functions hash It is believed to be resistant to quantum attacks.
Under this system, User also pre-commits on chain The recovery transaction then proves that you know the original seed phrase. Unlike the previous method, here the private key is not exposed directly, but information that allows the private key to be safely derived.
The entire process takes place within Bitcoin. rule change Determines which transactions are valid after freezing.
This method allows funds to be recovered even from addresses where the public key is already known, but has similar challenges to previous schemes. protocol change requiredcorrect implementation by specific software and wallets.
Methods before “QDay”
This approach targets older and weaker Bitcoins stored in P2PK (Payment to Public Key) addresses. It will remain visible from the moment you receive the funds.
This strategy requires users to act before the so-called “QDay,” the day when quantum computing is able to break current codes. In this context, “generating a commitment” means pre-publishing a hash on-chain via OP_RETURN. This acts as sealed proof of ownership of your private key without exposing your private key or moving your Bitcoins.
The report acknowledges that this method is impractical for most people, as anyone who can act before QDay can easily move funds to a secure address.
However, BitMEX presents a specific case: Satoshi Nakamoto. The analysis shows that Satoshi was able to make public commitments publicly without publicly linking his coins. If he was able to recover those funds in the future, that prior commitment would prove that he had access to the keys before the quantum age. Otherwise Bitcoin they will be frozen foreverquestions remain as to whether Satoshi still controls those keys.
Methods using zero-knowledge proofs (ZK-Proofs)
The latter scheme specifically uses zero-knowledge (ZK) proofs of the STARK type. This allows you to prove that the secret is known without revealing it. In this case, the user proves that they have a seed phrase for their wallet. without publishing any words.
Unlike previous methods, this mechanism requires a single transaction, does not expose sensitive information, and can be reused. For it to work, new types of expenses would need to be introduced. through protocol updateswe recognize that these tests are valid after quantum freezing.
According to BitMEX, this approach allows users to continue using their wallets as usual until a threat becomes a reality, avoiding a hasty transition. For the first time since the freeze, they were able to update their software at their own pace and continue using their Bitcoin safely.
Finally, BitMEX’s proposal can be read as a technical response to proposals such as that of developer Jameson Lopp, who proposed burning exposed BTC as a way to deal with quantum risk, as reported by CriptoNoticias.
