Quantum-Proofing Crypto Without Moving a Coin, and What That Requires
Blockchain security firm AmericanFortress has published a technical paper proposing a way to protect existing Bitcoin, Ethereum, and Solana wallets from future quantum attacks without forcing holders to move funds, rotate keys, or change addresses. The proposal, called Zero-Knowledge Proof of Seed Provenance, or ZK-PoSP, went live on the International Association for Cryptologic Research’s ePrint archive on July 28. It has not been peer-reviewed.
How ZK-PoSP protects existing wallet addresses
The scheme lets a wallet prove it knows the seed used to derive an address without revealing that seed. Rather than signing a transaction with a private key, the wallet submits a zero-knowledge proof. Nodes verify the proof and clear the transaction. The public key stops being the weak point because it no longer authorizes a spend.
That matters because a quantum computer running Shor’s algorithm could derive a private key straight from an exposed public key. Most proposed fixes involve switching to a post-quantum signature scheme, which changes the public key format and forces address migration across every participating network. Some coins can’t migrate at all. Roughly 1.1 million BTC tied to Satoshi’s early wallets haven’t moved since 2010, and dormant holders won’t be reading migration notices.
ZK-PoSP is designed to cover both the secp256k1 curve used by Bitcoin and Ethereum and the Ed25519 curve common on Solana. It supports hierarchical deterministic wallet standards including BIP32 and SLIP-10. AmericanFortress describes it as the first post-quantum approach that preserves existing addresses without asset transfers.
The company reports low computational costs from its own tests. Generating a one-time proof to secure an address runs about $0.002 on a 16-core server. Each transaction proof costs roughly $0.00125. Signing takes about 12 seconds, with verification between nine and 10 milliseconds. Those figures reflect lab tests, not a live blockchain integration, which could add storage, bandwidth, and coordination demands.
What still has to happen before ZK-PoSP can be adopted
The paper labels its post-quantum security “conjectured” rather than proven, since no cryptographically relevant quantum computer exists to test against. Deployment depends on node operators shipping the verification upgrade and wallet providers generating the proofs. Until a network enforces that, exposed addresses stay vulnerable.
The proposal lands amid growing institutional attention. Strategy, BlackRock, Coinbase, and six other companies recently formed the Bitcoin Security Consortium, pledging $15 million over three years. The Ethereum Foundation set up a post-quantum team in January and is testing hash-based signatures and migration tools. AmericanFortress holds a patent filing and plans to license its SDK, giving it a commercial stake in whether the industry adopts the approach. Independent review comes next.