Security must persist

Quantum resilient ≠ Quantum safe

Being “quantum-safe” is not enough — systems must remain secure through continuous change.

04 / 06
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Hybrid keys — quantum-resilient and backwards-compatible at once.

Status Quo, Resilient, Safe — what each actually means

04 / Quantum resilient ≠ Quantum safe

Two keys, one credential, no partner coordination needed

These terms are often used interchangeably; they are not the same. Status Quo is today's classical cryptography (RSA, ECDSA) with no resistance to quantum attacks. Quantum Resilient means a system can withstand some quantum attacks — achievable now with hybrid keys. Quantum Safe means the underlying algorithm is mathematically proven to resist all known quantum attacks, including Shor's and Grover's.

Larger key sizes — for example RSA-4096 — make RSA more resilient against classical attacks; a sufficiently powerful quantum computer still breaks it. Only NIST-certified PQC algorithms get close to truly quantum safe.

ML-KEM · ML-DSA · SLH-DSA RSA-4096 is still not safe
Status Quo
Classical cryptography in production today
✓Resists classical attacks
✗Vulnerable to Grover's algorithm
✗Broken by Shor's algorithm
✗RSA, ECDSA, Ed25519 only
✗Exposed to harvest-now-decrypt-later
Quantum Resilient
Achievable today with hybrid keys
✓Resists classical attacks
✓Hybrid PQC + classical signatures
✓ML-DSA-65 signing for new credentials
✓ML-KEM-768 key encapsulation
✓Backwards compatible with legacy partners
✓Protects new data from HNDL
~Older archived data stays at classical risk
Quantum Safe
Ideal state. No system today is fully quantum safe.
✓Resists classical attacks
✓Resists Grover's algorithm
✓Resists Shor's algorithm
✓NIST FIPS 203 / 204 / 205
✓Mathematically proven

Hover over any pill Term to see what it means.

Hybrid Keys Next: Harvest Now, Decrypt Later