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Quantum computing is rapidly emerging as the most disruptive threat to modern blockchain security, pushing the industry into an urgent race toward post‑quantum cryptography.

Over the past decade, blockchain security has been considered one of the most reliable pillars of the digital ecosystem. However, the rapid rise of quantum computing is reshaping this landscape. According to an IBM report published in 2025, quantum processors could reach a level of power by 2030 capable of breaking the cryptographic algorithms currently used by Bitcoin, Ethereum, and most decentralized networks.

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Why Quantum Computers Are a Real Threat

Quantum attacks are no longer science fiction. Shor’s algorithm, developed in 1994, theoretically allows quantum computers to:

• factor extremely large numbers in a fraction of the time

• break RSA, ECDSA, and other digital signature schemes

• derive private keys from public keys

Today, a classical computer would need billions of years to break a 256‑bit ECDSA key. A fully mature quantum computer could do it in hours.

Early Real‑World Tests

In 2025, a research team at the University of Waterloo demonstrated that a 1,000‑qubit quantum prototype can already:

• simulate attacks on reduced‑size keys

• identify vulnerabilities in signature protocols

• perform parallel computations impossible for classical hardware

We are not yet at the breaking point, but the direction is unmistakable.

The Response: Post‑Quantum Cryptography (PQC)

In 2024, the National Institute of Standards and Technology (NIST) selected the first official post‑quantum cryptography standards:

• CRYSTALS‑Kyber (key encapsulation)

• CRYSTALS‑Dilithium (digital signatures)

• Falcon (high‑efficiency signatures)

These algorithms are designed to withstand quantum attacks thanks to:

• lattice‑based mathematical problems

• complexity that quantum algorithms cannot reduce

• larger but significantly more secure keys

Blockchains Already Migrating to PQC

Ethereum

• Testing PQC security layers on ZK‑rollups.

• Vitalik Buterin has stated that migration will be “inevitable” before 2030.

Algorand

• Introduced a hybrid system combining classical and post‑quantum signatures.

QANplatform

• First blockchain natively designed to be quantum‑resistant.

• Uses Kyber and Dilithium as default standards.

Bitcoin

• The community is divided: some advocate for a soft fork, others fear centralization risks.

Economic Impact

According to Deloitte, the post‑quantum security market could reach:

• $9.5 billion by 2032

• with a 28% CAGR

Blockchains that fail to adapt may face:

• “harvest now, decrypt later” attacks

• large‑scale fund theft

• loss of investor confidence

The quantum revolution is not a theoretical risk — it is a deadline. Blockchains that adopt post‑quantum cryptography early will set the standards for the next generation of decentralized systems.

📚 Sources

• NIST – Post‑Quantum Cryptography Standardization

• IBM – Quantum Roadmap 2025–2030

• Deloitte – The Future of Post‑Quantum Security

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