QuantMagic

Focus Cybersecurity

Quantum-safe security

A large, error-corrected quantum computer would break the public-key encryption that secures today’s internet, payments and identities. Nobody knows exactly when. The fix exists, and moving to it takes years, so the time to start is now.

01 The threat

What breaks, and what doesn’t

Not all cryptography is equally exposed. The damage is concentrated in one place, and it is the place everything else depends on.

Public-key cryptography breaks

RSA, elliptic-curve cryptography and Diffie-Hellman secure TLS, VPNs, code signing, payments and digital identity. Their security rests on math problems that Shor’s algorithm solves efficiently on a large enough quantum computer.

RSA · ECC · DH → replace

Symmetric encryption holds

AES and the SHA-2 and SHA-3 hash functions are only weakened, by Grover’s algorithm, and longer keys restore the margin. AES-256 is considered safe.

AES-256 · SHA-384 → keep

The machine keeps shrinking

In 2019, breaking RSA-2048 was estimated to need about 20 million noisy qubits. A 2025 analysis by Craig Gidney at Google cut that to under one million, running for under a week. No machine that size exists yet, but the gap is closing from both sides.

20M qubits (2019) → under 1M (2025)

Harvest now, decrypt later

Attackers can record encrypted traffic today and decrypt it once a capable machine exists. Anything that must stay secret for ten years or more, such as financial records, health data, trade secrets and long-term keys, is already at risk.

02 The fix

Post-quantum cryptography is standardized

New algorithms, built on math that quantum computers are not known to break, run on today’s ordinary hardware. In August 2024 NIST published the first three standards.

ML-KEM

Key exchange: how two systems agree on a secret key. It replaces RSA and elliptic-curve key exchange in TLS and VPNs. Major browsers and content networks already use it, in hybrid mode alongside a classical algorithm.

FIPS 203 · from Kyber

ML-DSA

Digital signatures for certificates, code signing, documents and transactions. The general-purpose replacement for RSA and ECDSA signatures.

FIPS 204 · from Dilithium

SLH-DSA

A hash-based signature built on very conservative assumptions. Larger and slower, and a strong backup if a weakness is ever found in the others.

FIPS 205 · from SPHINCS+

The deadline

NIST’s draft transition plan (IR 8547) deprecates the weakest quantum-vulnerable algorithms, such as RSA-2048, after 2030 and disallows all of them after 2035. Large organizations typically take years to change cryptography, so for most of them that window is already tight.

03 Quantum and AI on defense

The same technology helps you defend

Quantum computing and AI are not only the threat. Used well, both speed up the response.

AI

Find every key

The slowest part of migration is discovery: every place cryptography hides in code, configuration, certificates and vendor products. AI-assisted scanning makes that inventory faster and more complete.

Quantum

Quantum randomness

Quantum random number generators draw randomness from physical processes, and are already sold as hardware and cloud services.

Quantum

Quantum key distribution

QKD uses physics rather than math to share keys over dedicated links. It suits a few specialist connections. For most systems, post-quantum cryptography is the practical path.

04 The plan

A migration in five steps

The same sequence works for a bank, an insurer or a software company. Its size depends on how much cryptography you have and how well you know where it is.

  1. Inventory

    Find every use of public-key cryptography: protocols, libraries, certificates, hardware security modules and third-party services.

  2. Prioritize

    Rank systems by how long their data must stay secret and how hard they are to change. Long-lived data and signing keys go first.

  3. Become crypto-agile

    Make algorithms swappable through configuration rather than rewrites, so this migration, and the next one, is routine.

  4. Migrate in hybrid mode

    Run classical and post-quantum algorithms together first, so security never drops below today’s level while the new ones prove themselves.

  5. Hold vendors to it

    Put post-quantum support and dates into procurement and contracts. Much of your exposure sits in products you buy, not code you write.

Talk to us

Get a quantum-readiness assessment

We help you find your exposure, set priorities and build a migration plan your teams and vendors can follow.

hello@quantmagic.ai