Grand Cayman, Cayman Islands, August 6th, 2026, Chainwire

Sui, a next-generation Layer 1 blockchain where money moves as freely as messages, has announced the adoption of two NIST-approved post-quantum signature schemes to enhance its quantum readiness. The upgrade will allow user accounts to transition to quantum-safe keys derived directly from their existing recovery phrases.

The timeline for quantum threats differs significantly for blockchains compared to traditional systems. In most conventional architectures, an attacker requires a system breach to access a public key. On a blockchain, however, a public key is permanently exposed the moment an account transacts. Shor's algorithm, which is capable of breaking the elliptic-curve cryptography securing most onchain accounts—as well as the broader internet and traditional banking systems—poses a severe risk.

The threat is not purely theoretical. "Harvest-now-forge-later" data collection tactics require only a visible key and patience, rather than existing quantum hardware, meaning the exposure of current keys is already accruing. In March 2026, Google Quantum AI estimated that recovering a private key from an exposed public key could execute in minutes on a fault-tolerant quantum machine utilizing fewer than half a million physical qubits. Current quantum processors remain well below this scale, yet agencies including CISA and NSA have urged organizations to begin migration planning well before such machines exist, citing the multi-year effort required to update cryptographic infrastructure across complex systems.

To proactively counter these emerging threats, Sui is adopting two distinct signature schemes tailored to different risk profiles. This multi-layered approach ensures that a mathematical weakness discovered in one algorithm does not compromise the entire network, as the two schemes rely on fundamentally different hard problems—lattice-based assumptions for ML-DSA and hash function security for SLH-DSA.

ML-DSA-65 (FIPS 204) for Native Accounts

For everyday transactions, ML-DSA-65 will serve as a native protocol signature scheme. Sui is integrating Level 3 security rather than the less computationally expensive Level 1. This decision follows a July 2026 incident in which an AI model halved the effective key strength of HAWK, a post-quantum signature candidate, in approximately 60 hours—a candidate that had previously cleared two years of rigorous expert human review. This choice aligns with broader internet infrastructure shifts; AWS KMS now offers ML-DSA signing in its hardware-backed key service, and Android 17's Keystore generates quantum-safe signatures inside secure hardware starting at ML-DSA-65, skipping the 44 parameter set entirely.

SLH-DSA-SHA2-128s (FIPS 205) for Smart Contract Vaults

For high-value assets, Sui will integrate SLH-DSA-SHA2-128s. These hash-based signatures will be managed directly within Move smart contracts rather than at the protocol core. This strategy leverages the well-understood security of hash-based cryptography and provides essential flexibility. By keeping the implementation in-contract, Sui can remain compatible with whichever post-quantum standards the wider industry ultimately adopts, without forcing a core protocol upgrade—a vital feature given Sui's bridges to other blockchain networks, where counterpart chains may migrate at different speeds or select different algorithms.

Both implementations adhere to NIST's standardized post-quantum algorithms—formalized as federal standards in August 2024 after a multi-year global selection process that began in 2016—and the joint CISA/NSA/NIST quantum-readiness roadmap.

User Experience and Network Impact

Sui was architecturally designed for cryptographic agility, allowing new signature schemes to be added without altering the network's consensus mechanisms or foundational state. For users, this transition avoids the traditional hurdles of cryptographic migrations. On Sui, an ML-DSA-65 private key is a 32-byte seed—the exact size wallets currently store—derived from a user's standard recovery phrase via a new derivation path. Wallet backup and restoration processes will remain identical to current operations.

Existing accounts will not need to move funds. Utilizing Address aliases, already deployed on the Sui network, users can update their authorization keys to post-quantum keys while retaining their original address and assets in place. There will be no forced migrations or costly asset transfers.

While the transition provides robust security, it does introduce larger data sizes. Post-quantum signatures and public keys are substantially larger than traditional Ed25519 pairs, increasing overall transaction sizes—an industry-wide trade-off for quantum resistance. However, ML-DSA-65 verification on Sui is highly optimized, keeping per-signature network costs comparable to Ed25519. Sui's programmable transaction blocks and transaction size limits will absorb the remaining differences as further optimization work continues.

Deployment Timeline

The core implementation for Sui's post-quantum features is built and benchmarked. Quantum-safe vaults are targeted for Mainnet deployment later this year. Native ML-DSA-65 accounts are expected to reach Testnet by the end of 2026, with native account authentication on Mainnet slated for Q1 2027. Wallet, SDK, and CLI support will roll out concurrently. Sui notes that these timelines remain flexible pending independent security audits and Testnet feedback.

Post-quantum accounts will arrive as an additive, opt-in capability, utilizing the same rollout path previously established for zkLogin and passkeys. Existing applications will not require immediate adjustments. For further technical background on how Sui primitives transition to post-quantum cryptography, users can refer to the official documentation: Securing Sui in the Quantum Computing Era.

About Sui

Sui is a Layer 1 blockchain optimized for scalable finance and global payments. Founded by the core engineering team behind Meta's stablecoin initiative, Sui utilizes an object-centric model that renders assets, permissions, and user data programmable and ownable. The network provides developers with the foundational tools to build high-performance financial applications, including instant agentic payments.

Contact:
[email protected]
Sui Foundation