QuFi Network, a company specializing in post-quantum infrastructure, has launched a verification platform designed to protect digital assets from future quantum computing threats without requiring changes to existing settlement blockchains. The platform separates verification and settlement processes, using a decentralized network of nodes to validate transactions with post-quantum cryptography before their final settlement on existing blockchains.
As a proof-of-concept, QuFi introduced uBTC — a system that applies the verification system to Bitcoin and is currently running on Bitcoin Testnet4. The uBTC system verifies BTC collateral and generates cryptographic proofs that govern the movement of value between settlement environments, while redemptions ultimately settle as standard Bitcoin transactions. The platform uses three post-quantum cryptographic standards: ML-DSA-65, SLH-DSA and ML-KEM-1024 for digital signatures and secure key exchange.
Key innovation: QuFi separates verification from settlement, creating an external security layer. This makes it possible to protect assets from quantum threats without having to upgrade existing blockchains, avoiding additional storage, bandwidth and computing requirements.
QuFi's fundamental innovation lies in the architectural separation of verification and settlement processes. The traditional approach to post-quantum security requires implementing new cryptographic algorithms directly into the base blockchain, creating significant technical challenges. Post-quantum signatures are considerably larger than existing ECDSA or Schnorr signatures, resulting in increased storage, bandwidth and computational resource requirements.
QuFi addresses this problem by creating an external verification layer — a decentralized network of nodes that performs transaction verification using post-quantum cryptography before transactions are submitted to the underlying blockchain for final settlement. This approach allows existing blockchains to continue operating with their native cryptography, while the verification layer provides protection against quantum attacks.
The process works as follows: a user initiates a transaction, which first passes through the QuFi verification network. Network nodes validate the transaction using post-quantum algorithms and generate a cryptographic proof confirming the transaction's validity. Only after successful verification is the transaction sent to the underlying blockchain for final settlement. This approach creates an additional layer of security without requiring consensus among all participants of the base blockchain to adopt new cryptographic standards.
QuFi uses three post-quantum cryptographic standards selected through the NIST post-quantum cryptography standardization process. ML-DSA-65 (Module-Lattice-Based Digital Signature Algorithm) is used for digital signatures with a medium security level, providing a balance between security and performance. SLH-DSA (Stateless Hash-Based Digital Signature Algorithm) is a hash-based signature scheme relying only on the security of hash functions, making it a conservative choice for long-term security.
ML-KEM-1024 (Module-Lattice-Based Key-Encapsulation Mechanism) is used for secure key exchange with a high security level, providing protection against quantum attacks on the key exchange process. The combination of these three standards creates defense in depth, with each algorithm protecting different aspects of cryptographic operations.
As a proof-of-concept, QuFi launched uBTC on Bitcoin Testnet4. The system demonstrates how the verification platform can be applied to Bitcoin by verifying BTC collateral and generating cryptographic proofs that govern the movement of value between different settlement environments. When a user wants to redeem their funds, the system generates a standard Bitcoin transaction for final settlement on the main Bitcoin blockchain. This approach allows users to benefit from post-quantum security during the verification phase, while final settlement takes place through ordinary Bitcoin infrastructure.
Technical elegance of uBTC: The system does not require changes to the Bitcoin protocol. All post-quantum verification takes place in the external layer, while final settlement uses standard Bitcoin transactions, ensuring compatibility with the existing Bitcoin ecosystem.
QuFi's external verification layer approach addresses several critical challenges associated with directly implementing post-quantum cryptography into existing blockchains. The first and most obvious problem is signature size. Post-quantum signatures can be 10-100 times larger than existing ECDSA signatures, significantly increasing block size requirements. For Bitcoin, with its conservative approach to block size, this would create fundamental scalability issues.
The second problem is related to computational requirements. Verifying post-quantum signatures requires significantly more computational resources than traditional signatures. This would increase hardware requirements for nodes and miners, potentially leading to greater centralization because only organizations with powerful hardware might be able to participate in the network.
The third problem is the coordination challenge. Implementing post-quantum cryptography requires consensus among all network participants, which in decentralized networks like Bitcoin could take years or even decades. An external verification layer allows individual users and organizations to adopt post-quantum security immediately without waiting for network-wide consensus.
QuFi's approach also provides flexibility and gradual adoption. Users can choose whether to use post-quantum verification for their transactions while the underlying network continues operating normally. This creates a path for gradual migration to post-quantum security without requiring a hard fork or other disruptive changes.
The launch of QuFi represents a significant milestone in the evolution of post-quantum security for the crypto industry. As quantum computing technology advances, the threat to existing cryptography is becoming increasingly realistic. Although estimates vary, many experts predict that cryptographically relevant quantum computers could emerge within 10-20 years. Preparation for this threat needs to begin long before it materializes because of the complexity of coordination and migration in decentralized systems.
QuFi's external verification layer approach could become a blueprint for other projects facing similar challenges. Instead of waiting for network-wide consensus on post-quantum upgrades, projects can implement external security layers that provide protection to willing participants without forcing changes on the entire network. This approach is especially valuable for established networks like Bitcoin, where consensus on major protocol changes is extremely difficult to achieve.
The uBTC proof-of-concept on Bitcoin Testnet4 demonstrates the practical viability of this approach. If the system proves its effectiveness and security on testnet, it could be deployed on mainnet, giving Bitcoin users an option for post-quantum protection of their transactions. This could be particularly important for high-value transactions or organizations seeking to future-proof their crypto holdings.
Strategic significance: QuFi demonstrates that post-quantum security does not necessarily require fundamental changes to existing blockchains. External verification layers can provide protection without disruption, creating a pragmatic path forward for the entire industry.
For the broader crypto ecosystem, QuFi's success could accelerate the adoption of post-quantum cryptography across a range of projects. DeFi protocols, enterprise blockchain solutions and other applications could implement similar external verification layers to protect against quantum threats. This could lead to a new industry standard in which post-quantum security becomes widely available without requiring network-wide upgrades.
QuFi's initiative also highlights the importance of proactive security planning in the crypto industry. Instead of reacting to quantum threats after they emerge, projects can begin preparing now by testing and refining solutions in testnet environments. This proactive approach significantly reduces risks and provides a smoother transition to the post-quantum era.
In the long term, external verification layers could become a standard component of blockchain infrastructure, much like Layer 2 solutions have become an integral part of the Ethereum ecosystem. Just as L2s address scalability challenges without changes to the base layer, external verification layers could address post-quantum security challenges without requiring consensus on protocol changes.
“The best security is the security you implement before it becomes necessary. In the world of quantum computing, proactive preparation is not a luxury but a necessity.”
— Adam Back, cryptographer and CEO of Blockstream
