Guide to PQC (Post-Quantum Cryptography) Migration

The Quantum Heist: Why Your Encrypted Data Isn’t Safe

Right now, somewhere in a server farm, your company's most sensitive data sits encrypted and "safe." Your bank transfers. Your critical assets are locked behind what you believe is unbreakable math.

But here's the truth: hackers have already copied it all. Sound dramatic? Ask Northern Rail how it felt to watch 420 stations go dark because ransomware crippled their systems. Now imagine those attackers had quantum computers. (Source: Security Week News)

How Ransomware Attacks Are Evolving

Criminal syndicates and nation-state actors are recording every encrypted message flowing through the internet. Your confidential emails, medical records, financial transactions, defence communications—everything. It’s basically photocopying your locked safe, taking it home, and waiting until they invent a tool to open it.

The 'Harvest Now, Decrypt Later' Threat Explained

That's exactly what's happening with "Harvest Now, Decrypt Later" attacks. They can't read any of it. Yet.

Quantum Computers vs. RSA: The Coming Breakthrough

NIST researchers have done the math - a powerful quantum computer could crack RSA-2048 encryption in less than 8 hours, a task that today's computers take longer than the universe to accomplish.

New NIST Post-Quantum Cryptography Standards You Need to Know

NIST just released three groundbreaking standards:

• ML-KEM – Locks down key exchanges so quantum computers can't intercept
• ML-DSA – Creates unforgeable digital signatures
• SLH-DSA – Provides long-term security even against future quantum attacks

What Is ML-KEM?

ML-KEM secures key exchanges, making it resistant to interception by quantum adversaries.

Unbreakable Digital Signatures with ML-DSA

ML-DSA creates digital signatures that remain unforgeable in a post-quantum world.

Future-Proof Security: SLH-DSA Overview

SLH-DSA offers long-term security using hash-based structures designed to resist quantum attacks.

Why Migration Needs More Than a Software Patch

These aren’t tweaks to existing encryption algorithms—they require rebuilding cryptographic infrastructure based on lattice mathematics and hash functions that quantum computers can't efficiently solve.

How to Prepare: Your PQC Migration Roadmap

Migration is a multi-year engineering project requiring:

• Inventorying every cryptographic asset
• Testing new algorithms in your systems
• Coordinating upgrades across vendors, hardware, and embedded devices
• Running hybrid systems that use both old and new encryption during transition

Seven Steps to Post-Quantum Resilience

1. Engage with evolving quantum-safe standards (4-6 weeks)
2. Inventory critical data assets across industries
3. Inventory cryptographic technologies across infrastructure and applications
4. Update organizational cryptography standards
5. Identify quantum-vulnerable public key cryptography (e.g., RSA, ECC)
6. Prioritize systems using a risk-based crypto agility framework
7. Plan a comprehensive 4-phase migration (0-24 months)

90-Day Post-Quantum Action Plan

Month 1: Assess

• Inventory all cryptographic assets
• Identify systems with 10+ year data lifetimes
• Calculate your X + Y vs. Z equation (Mosca's Theorem-If the years your data must stay secret (X) + years to migrate (Y) is greater than years until quantum computers arrive (Z), adversaries harvesting your data TODAY will decrypt it TOMORROW)

Month 2: Pilot

• Deploy hybrid PQC in one critical system
• Test performance and compatibility
• Train teams on quantum-safe practices

Month 3: Plan

• Build phased migration roadmap
• Engage vendors on PQC support timelines
• Allocate budget for 3–5-year transition

Your encrypted secrets aren't safe. But they can be.

Every day you delay, your encrypted data is already getting copied, waiting for quantum computers to unlock it all at once. Your board won't forgive "we didn't know" when a decade of customer data, IP, or classified communications gets exposed overnight.  

The organizations that survive the quantum transition are the ones acting now, while they still control the timeline. Book your confidential PQC and Cryptoagility assessment with QNu Labs, because the worst cyberattack in your company's history might have already started. You just don't know it yet.

PQC Migration FAQs: Everything You Need to Know

Q: What actually is Post-Quantum Cryptography?

A: Encryption algorithms designed to survive quantum computer attacks—unlike today's RSA and ECC methods that will crumble.

Q: How is "Harvest Now, Decrypt Later" even possible?

A: Attackers copy encrypted data now (cheap and easy), then wait for quantum computers to decrypt it later (patient and devastating).

Q: Do I really need to worry about this today?

A: If your data needs to stay secret for more than 10 years, you needed to worry yesterday. NIST says federal systems must migrate by 2035.

Q: What are these new NIST algorithms everyone mentions?

A: ML-KEM (secure key sharing), ML-DSA (quantum-proof signatures), and SLH-DSA (long-term hash-based security). They're now official U.S. federal standards.

Q: Can we run old and new encryption together?

A: Yes—hybrid solutions combine classical and PQC algorithms, protecting you during transition without breaking existing systems.

Q: How does QNu Labs actually help with migration?

A: We inventory your crypto assets, assess quantum risk, deploy hybrid solutions, provide QKD for ultra-high-security needs, and ensure regulatory compliance throughout.

Q: Which sectors face the worst quantum threats?

A: Banking (transactions), defense (classified comms), railways (safety systems), telecom (infrastructure), healthcare (records)—basically anyone with long-lived sensitive data.

Q: What's a Cryptographic Bill of Materials?

A: A complete inventory of every encryption algorithm, key, and certificate in your systems—your essential first step before migration.

Q: Do quantum computers that can break encryption exist right now?

A: Not yet at the required scale—but experts predict 10-15 years. Which means data encrypted today becomes vulnerable then.

Q: Won't PQC migration cost a fortune?

A: Migration costs vary, but data breaches cost more. Early migration minimizes disruption, maximizes time for testing, and reduces catastrophic risk.