Solana is now ‘Quantum Resistant’—what does that mean?

Solana Developers have created a quantum-resistant vault that uses a decades-old cryptographic technique to protect users' money from quantum computer attacks. The solution, called Solana Winternitz Vault, implements a hash-based signature system that generates new keys for each transaction.

Vault addresses a known vulnerability in blockchain technology: quantum computers can break the cryptographic algorithms that keep digital wallets secure. When users sign transactions, they expose their public keys, which theoretically enough powerful quantum computers can access their private keys via the Elliptic Curve Digital Signature Algorithm. (These stories may help you understand this topic a little more.)

Vault is currently an optional feature, not a network-wide security update, so there's no fork in sight. This means that users must actively choose to store their funds in these Winternitz Vaults instead of standard Solana wallets for quantum proofing.

“It's not lost on me that we're using Lamport's work to capture Lamports,” said project developer Dean Little, explaining that Vaught Winternitz uses a one-time signature encryption protocol.

The system works by generating 32 private key scalars and hashing each 256 times to create a public key. Instead of storing the entire public key, the program stores only one hash for verification. Each time a transaction occurs, the vault closes and opens anew with new keys.

If all these words sound strange, consider this imprecise but adequate analogy: if you ask for a new credit card every time you pay, no hacker can guess the number before you pay.

“While no one can hash backwards, anyone can hash forwards from a previous value,” Little explained. This means that each signature has a 50% chance of being compromised for future transactions.–That's why Vault generates new keys after each use.

Quantum resistance before freezing

While Solana's implementation marks an important step for the network, quantum-resistant cryptography in blockchain is not new. David Cham, often referred to as the “godfather of crypto,” launched Praxis in 2019 specifically to address the concerns of quantum computing. His team has developed a consensus protocol that promises to overcome scalability, privacy and security challenges while being resilient to quantum attacks.

The discussion around quantum resistance in crypto has been going on for some time. Google gained momentum after announcing that it would acquire Quantum Dominance in 2019. His 53-qubit computer demonstrated unprecedented computing power, performing calculations in 200 seconds that would take traditional computers more than 10,000 years. Recently, Google's Willow chips were able to achieve in 5 minutes calculations that would take 7 septillion years using the fastest supercomputers available today.

However, Cornell University researchers have suggested that breaking a 160-bit elliptic curve cryptographic key would require 1,000 qubits—much more than is currently available. Despite this, many blockchain projects are not waiting. QAN, for example, claims to have achieved “quantum strength” in its beta stage, while other protocols are quietly improving their cryptographic foundations.

Some experts argue that quantum computing power could grow at a double-exponential rate.–This is known as Neven's Law. This prediction has prompted more blockchain developers to implement quantum-resistant solutions, even though full-scale quantum computers are years or decades away from posing a real threat to current cryptographic standards.

So focusing on quantum resistance may seem like overkill for many crypto projects, but Web3 developers are two steps ahead. If you don't believe me, ask why chains that don't process more than a few hundred transactions per second devote so much resources to supporting thousands or even millions of transactions per second.