Quantum computers can break most modern encryption algorithms. This isn’t science fiction - major companies are already preparing for the “quantum apocalypse.” Let’s understand what this means for your security.
The Problem: Why Quantum Computers Are Dangerous
How Modern Encryption Works
Most secure connections (HTTPS, VPN, banking) use asymmetric cryptography - RSA and elliptic curves (ECDH).
Security is based on mathematical problems that classical computers solve in billions of years:
- Factoring large numbers (RSA)
- Discrete logarithm (ECDH)
What Quantum Computers Change
Shor’s algorithm allows a quantum computer to solve these problems in hours or minutes.
| Algorithm | Classical Computer | Quantum Computer |
|---|---|---|
| RSA-2048 | 300 trillion years | 8 hours |
| ECDH-256 | Billions of years | Minutes |
Fact: Sufficiently powerful quantum computers don’t exist yet, but they’re being actively developed. Predictions range from 5 to 15 years.
”Harvest Now, Decrypt Later” Threat
Attackers and intelligence agencies can record encrypted traffic today to decrypt it when quantum computers become available.
If your data must remain secret for 10-20 years - it’s already at risk.
The Solution: Post-Quantum Cryptography
What It Is
Post-quantum algorithms (PQC) are based on mathematical problems that are difficult for both classical and quantum computers:
- Lattice-based: problems in multidimensional structures
- Code-based: decoding random linear codes
- Hash-based: digital signatures based on hashes
- Isogeny-based: problems on elliptic curves
NIST Standards
In 2024, the U.S. National Institute of Standards and Technology (NIST) approved the first post-quantum standards:
| Algorithm | Purpose | Basis |
|---|---|---|
| ML-KEM (Kyber) | Key exchange | Lattices |
| ML-DSA (Dilithium) | Digital signatures | Lattices |
| SLH-DSA (SPHINCS+) | Digital signatures | Hash functions |
How It Works in VPN
Hybrid Encryption
Modern implementations use a hybrid approach: classical algorithm + post-quantum.
Connection = ECDH + ML-KEM (Kyber)
Why hybrid:
- If PQC proves vulnerable - classical algorithm protects
- If quantum computer breaks classical - PQC protects
- Double insurance for the transition period
Performance Impact
Post-quantum algorithms require more resources:
| Parameter | Classical (ECDH) | Post-Quantum (Kyber) |
|---|---|---|
| Key size | 32 bytes | 1568 bytes |
| Connection setup time | ~1 ms | ~2-3 ms |
| CPU load | Low | Moderate |
In practice, the difference is imperceptible to users - a couple milliseconds delay when establishing connection.
Which VPNs Already Support PQC
Implementation Leaders (2026)
| Provider | Algorithm | Platforms |
|---|---|---|
| NordVPN | ML-KEM | Windows, Android, iOS, macOS |
| Proton VPN | NTRU (monitoring) | In development |
| Signal | PQXDH | Messenger |
| Apple iMessage | PQ3 | iOS, macOS |
Protocols with PQC Support
- WireGuard: experimental support
- OpenVPN: via plugins
- Proprietary: provider’s own implementations
Do You Need Post-Quantum Encryption
Critically Important For
Government agencies: classified data must remain secret for decades.
Financial sector: banking transactions, client personal data.
Healthcare: medical records, genetic information.
Journalists and activists: sources and correspondence can be dangerous even after 20 years.
Businesses with long-term secrets: R&D, patents, strategic plans.
Can Wait
Regular users: most data loses value within a few years.
Short-term correspondence: if information isn’t secret after 5 years.
However: Transition to PQC is inevitable. Better to start early than be vulnerable when quantum computers arrive.
What to Do Now
For Regular Users
- Watch for updates: enable PQC when your VPN provider offers it
- Update apps: new versions contain improved cryptography
- Don’t panic: quantum computers haven’t broken the internet yet
For Business
- Inventory: where is cryptography used that will become vulnerable
- Migration planning: create a PQC transition plan
- Prioritization: start with most valuable and long-lived data
- Testing: verify PQC compatibility with your systems
For the Paranoid
- Use VPN with PQC now: NordVPN and others offer it
- Encrypt archives: with algorithms resistant to quantum attacks
- Minimize data: what’s not recorded can’t be decrypted
Myths About Quantum Threat
Myth 1: “Quantum Computers Will Break Everything”
Reality: Symmetric encryption (AES-256) remains secure. Quantum computers only threaten asymmetric algorithms (RSA, ECDH).
Myth 2: “The Threat Is Far in the Future”
Reality: “Harvest now, decrypt later” attacks work today. Data is being recorded right now.
Myth 3: “Post-Quantum Algorithms Are Unproven”
Reality: Main algorithms have been studied for over 10 years. NIST conducted a multi-year competition with cryptographers worldwide.
Myth 4: “Transition Will Be Difficult and Expensive”
Reality: For end users, transition is transparent - just an app update. Complexity is on the developers’ and infrastructure side.
Quantum Threat Timeline
| Year | Event |
|---|---|
| 1994 | Shor’s algorithm - theoretical threat to RSA |
| 2016 | NIST launches PQC competition |
| 2024 | NIST approves first standards |
| 2025 | First VPNs implement PQC |
| 2030-2040 | Predicted arrival of cryptographically relevant quantum computers |
Summary
The quantum threat is real but not imminent. Post-quantum cryptography already exists and is being deployed. Transition will take years, but it needs to start now - especially for data with long secrecy requirements.
For most users, it’s enough to use modern VPN services and watch for updates. The cryptographic community is working on protection, and solutions will be ready by the time the threat arrives.
Tainet monitors post-quantum cryptography developments and is ready to implement new standards as soon as they become practical for mass use.
