Here’s the problem every blockchain eventually has to face: quantum computers, someday, might just break the signatures protecting your wallet. Sui is getting ahead of that. And it’s doing it in a way that doesn’t force anyone to pack up and move to a new address.
How Accounts Keep Their Address
Sui’s plan involves two systems, not one. For everyday accounts, it’s ML-DSA-65, standardized by NIST under FIPS 204. For the bigger stuff, higher-value vaults built through Move smart contracts, it’s SLH-DSA-SHA2-128s under FIPS 205. Both are built to resist the kind of large-scale quantum attacks that could, eventually, threaten the elliptic-curve signatures most of crypto still relies on today.
Normally this kind of upgrade is a pain. You’d need a new address, you’d have to move your tokens, your NFTs, everything. Contracts tied to your old address? Those need updating too. Sui’s getting around that with something it already has, Address Aliases. An account can authorize another signer to act on its behalf. Over time, that new signer can become the only one allowed to approve transactions, but the original address stays put. Same sender, new key underneath.
When ML-DSA accounts go live, an existing account will simply authorize a post-quantum signer this way. No new address needed. That matters a lot for accounts already wired into smart contracts or identity systems, places where changing addresses creates a mess nobody wants to deal with.
Recovery stays familiar too, which is a nice touch. An ML-DSA-65 key can be pulled from your existing recovery phrase, just through a new derivation path. You don’t need some totally separate backup system. One warning though, and it’s a real one: an authorized alias gets full control over the account. So wallet software’s going to need to make this process hard to mess up, or hard to exploit.
Why Two Different Quantum-Safe Systems
Sui isn’t betting on just one approach here, and that’s deliberate. ML-DSA-65 is lattice-based, built for regular day-to-day signing. It sits at NIST Security Category 3, a notch above the smaller ML-DSA-44 setup, while still being fast enough for constant verification. Worth mentioning too, Sui pointed to a recent AI-assisted discovery of a flaw in HAWK, a rival post-quantum candidate. Didn’t touch ML-DSA at all. But it proved something important, automated cryptanalysis can move fast, faster than the human review these designs already went through.
For the vaults, Sui’s going with SLH-DSA-SHA2-128s. Category 1, lower than ML-DSA-65’s rating, but that’s not really the point. It’s hash-based, not lattice-based, which means it doesn’t share the same underlying assumptions. If a weakness ever turns up in one system, it wouldn’t necessarily doom the other. Smart risk management, basically.
There’s a cost though. Size. An ML-DSA-65 signature runs 3,309 bytes, its public key adds another 1,952 bytes, compared to a measly 64 bytes for a standard Ed25519 signature. SLH-DSA-SHA2-128s is even bigger, 7,856 bytes per signature. Still, that’s a lot smaller than the 16-30 KB numbers sometimes thrown around for SLH-DSA, those numbers belong to stronger parameter sets, not the one Sui picked. Sui says ML-DSA verification speed stays close to Ed25519, so per-signature costs shouldn’t balloon, even though transactions themselves will get bigger. More optimization work is still happening behind the scenes.
No Action Required Yet
Timeline-wise: quantum-safe vaults are targeted for Mainnet before 2026 wraps up. Native ML-DSA-65 accounts should hit Testnet around the same time, with full Mainnet rollout following in early 2027. Wallets, SDKs, command-line tools, all planned to arrive alongside. But audits and Testnet feedback are still ongoing, so don’t treat these dates as locked in stone just yet.
For now, if you’ve got a Sui account, there’s nothing to do. Nothing at all. These new authentication methods are opt-in, additive, not some forced migration rolling out network-wide. And honestly, that design choice doubles as a built-in scam detector. Since Sui’s actual migration path never asks you to send funds to some new address, any message telling you to urgently move your coins to “go quantum safe” is immediately suspicious. No real quantum computer exists today that can break Sui’s current signatures. The real question isn’t if quantum computing gets there eventually, it’s whether Sui finishes this migration before it does.