The Quantum Era Is Coming: The Ultimate Defense Battle for Blockchain

When quantum computers truly mature, they will fundamentally change the world of cryptography in an unstoppable way. For blockchains that rely on cryptographic algorithms, this is not a distant future issue but an immediate survival crisis that must be addressed now.

How Quantum Computers Threaten Bitcoin

Bitcoin’s security architecture is built on the ECDSA encryption standard proposed in 1985. The core logic of this system appears invulnerable: users hold private keys (known only to themselves), and public keys are published for transaction verification. The strength of 256-bit keys means that traditional computers would require more than the age of the universe to brute-force crack them.

But quantum computers change the game.

With Shor’s algorithm, a sufficiently powerful quantum computer can derive the private key directly from the public key within a reasonable time. The UK National Cyber Security Centre has recommended that organizations determine quantum-safe upgrade plans by 2028 and complete migration around 2035. More pessimistic estimates suggest that the time when quantum computers pose a real threat may be around 2030.

This leaves less than ten years for the blockchain industry to prepare.

Three Hidden Dangers of Attacks

Covert Attacks: Once an attacker obtains the private key, they can silently forge transactions. The entire network will believe this is normal operation by the asset owner until it’s too late.

Selective Sniping: Public keys exposed in early Bitcoin addresses will become prime targets. Especially Satoshi’s over one million bitcoins—once movement begins, the market will panic. Even if the blockchain technology remains secure, the chain reaction triggered by a price crash could destroy the entire ecosystem’s confidence.

Time-Delay Profits: Attackers can copy publicly available blockchain data now and decrypt it later when quantum technology matures. Old addresses, long-unused wallets, and certain smart contract patterns will become highly vulnerable.

Survival Strategies of Major L1s

Faced with the threat of quantum computers, different blockchains have adopted varied response strategies.

Multi-Path Experimentation

Ethereum is developing a post-quantum migration roadmap, advancing in new transaction types, rollup experiments, and zero-knowledge proof packers. This strategy’s advantage is flexibility—avoiding reliance on a single solution and finding optimal approaches through practical experimentation.

Solana has launched an optional quantum-resistant vault—the Solana Winternitz Vault solution. Using a complex hash-based signature system, each transaction generates a new key, providing an optional safe haven.

Gradual Upgrades

Sui has released a dedicated quantum-safe upgrade path. Collaborating with academic partners, this plan avoids disruptive hard forks and adopts a gradual transition—protecting existing users while steadily building quantum security defenses.

Algorand has verified post-quantum technology in production. Introduced in 2022, the “State Proofs” use the NIST-standardized lattice-based signature scheme FALCON. Recently, it demonstrated a complete post-quantum transaction on the mainnet, providing quantum-safe verification services for other chains.

Cardano, although still using Ed25519 signatures, has long-term plans that incorporate independent proof chains, Mithril certificates, and NIST-standard post-quantum signatures, viewing quantum preparedness as a competitive advantage.

Rebuilding Approach

Some emerging projects choose to build fully quantum-resistant systems from scratch, without the burden of backward compatibility.

Quranium uses the NIST-approved stateless hash-based digital signature algorithm SPHINCS+, designed from the protocol level for the quantum era.

Quantum Resistant Ledger (QRL) launched in 2018, based on hash-based XMSS signatures, making it one of the earliest anti-quantum blockchains.

These projects are directly establishing colonies in the “new universe,” waiting for the arrival of the quantum age.

Practical Guide for Individual Users and Investors

User Level

Regularly checking and updating wallets is the first step to avoid becoming a prime target for quantum attacks. In the coming years, new account types, hybrid signature options, and upgrade prompts will gradually appear, especially for key rotation of high-value assets.

The key is to choose ecosystems that can add and rotate cryptographic primitives without requiring disruptive hard forks—this determines your liquidity in the quantum era.

Investor Due Diligence

Assessing a project’s preparedness against quantum threats requires examining three dimensions:

Roadmap transparency—Does the project have a clear documented post-quantum migration plan? Or only vague technical visions?

Actual progress—Are there prototypes or live features, or is it just marketing hype?

Timeline—Has the project set specific schedules for the quantum threats of the 2030s?

Resilience Without Single Points of Failure

The quantum computing crisis facing blockchain is not the end but the beginning of淘汰 and evolution. No single project holds the only correct answer, but that’s the power of decentralized systems—multiple paths exploring simultaneously, with the strongest solution ultimately prevailing.

As long as the core principles remain—decentralization, censorship resistance, trustlessness—the civilization will continue. The quantum era tests the speed of preparedness, not the persistence of ideals.

The true survivors are those who start acting now.