Blockchain security firm AmericanFortress has published a paper presenting a new approach to quantum resistance for cryptocurrency wallets, arguing that users may not need to migrate addresses or rotate keys to remain secure in a post-quantum world.
Quantum computing and the migration challenge
Quantum computing has long been identified as a potential risk for cryptocurrencies. If a sufficiently powerful quantum computer running Shor’s algorithm were to be developed, it could derive private keys from public keys, undermining the security of virtually all existing wallets. The standard response to this scenario has involved migrating assets and changing wallet addresses to employ quantum-safe cryptography.
However, the scale of address migration presents significant obstacles. Many cryptocurrency assets, such as Satoshi Nakamoto’s 1.1 million BTC and other dormant holdings, have not moved for years. The holders of these assets are unlikely to be reachable or take action in time, resulting in vulnerable funds even if large-scale migrations are attempted.
Zero-Knowledge Proof of Seed Provenance
The AmericanFortress paper introduces ZKPoSP, or Zero-Knowledge Proof of Seed Provenance, as a solution. Instead of signing transactions with a private key, wallets would use zero-knowledge proofs to demonstrate knowledge of the underlying seed phrase without ever exposing it. Since every address in a wallet is generated from this seed, the proof confirms control over the wallet while keeping sensitive data secure.
Transactions would rely on nodes verifying these proofs, not traditional cryptographic signatures. As a result, wallet addresses could remain unchanged, since public keys would no longer serve as the primary method for authorizing transactions. The authors assert that no address migration or key registration would be needed under this system.
By eliminating signatures in favor of zero-knowledge proofs, wallets could protect funds without altering existing addresses, sidestepping the need for migration in a quantum attack scenario.
A secondary proposal, dubbed QBIP32, is offered to provide quantum-safe key derivation across different cryptographic standards. Bitcoin and Ethereum use the secp256k1 curve, while Solana relies on Ed25519. QBIP32 aims to unify quantum-safe proof generation regardless of network type. The paper notes that current standards like BIP32 and SLIP-10 already enable these zero-knowledge proofs, so most existing wallets would not require immediate changes.
Mini dictionary: Zero-knowledge proof (ZK proof), a cryptographic method by which one party proves to another that a statement is true without revealing any information beyond the validity of the statement itself. ZK proofs are increasingly used in blockchain for privacy and security enhancements.
Implementation and next steps
The AmericanFortress approach remains theoretical. The company notes that full protection against quantum attacks is currently a matter of conjecture as no quantum computer capable of breaking contemporary cryptography exists yet.
Broader adoption also faces technical and commercial hurdles. For the proposed protocol to become effective, both blockchain nodes and wallet providers must update their software to support the new proof system. Only after widespread network and wallet upgrades could end users remain protected without taking independent action. AmericanFortress has submitted a patent for the technology and is offering software development kits (SDKs) under a commercial license, positioning itself to benefit from future adoption.
The proposed architecture requires coordinated upgrades from both wallet software and blockchain networks before users can benefit from quantum-safe protections without manual intervention.
