Quantum Computers Will Break RSA. Some Are Already Harvesting Your Data.

Nation-states are intercepting and storing encrypted traffic today, waiting for fault-tolerant quantum machines to decrypt it later.

This is "Harvest Now, Decrypt Later" - and it's why migration can't wait for 2030.

NIST's Finalized Standards

NIST's finalized standards (Aug 2024):

• FIPS 203 - ML-KEM (Kyber) for encryption and key exchange
• FIPS 204 - ML-DSA (Dilithium) for primary signatures
• FIPS 205 - SLH-DSA (SPHINCS+) as hash-based backup
• FIPS 206 - FN-DSA (FALCON) for compact IoT signatures

The 4-Phase Migration

• Cryptographic Bill of Materials - Passive scanners catalog every TLS cipher suite, PKI cert, and code-signing key. Prioritize data with 10+ year shelf life.
• Hybrid deployment - Never hard-cutover. Combine X25519 with ML-KEM-768. Attackers must break both simultaneously. Browsers and CDNs already support this.
• Packet fragmentation optimization - ECDSA signatures are ~64 bytes. ML-DSA-44 is over 2,400 bytes. That 40x increase breaks legacy firewalls and MTU limits.
• Cryptographic agility - Decouple algorithms from source code via OpenSSL 3.x providers or PKCS#11. If lattice math falls, swap in hash-based backups with zero downtime.

PQC vs. QKD

PQC runs on existing hardware as software. QKD needs dedicated fiber-optic lasers and single-photon equipment.

Full read: https://www.nizover.com/en/blog/tech-post-quantum-cryptography-nist-migration-guide