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

A blog post outlines a four-phase migration to post-quantum cryptography, warning that nation-states are already intercepting and storing encrypted traffic for later decryption under a "Harvest Now, Decrypt Later" strategy. It cites NIST's finalized standards from August 2024 — FIPS 203 (ML-KEM/Kyber), FIPS 204 (ML-DSA/Dilithium), FIPS 205 (SLH-DSA/SPHINCS+) and FIPS 206 (FN-DSA/FALCON) — and recommends hybrid deployments pairing X25519 with ML-KEM-768, packet fragmentation work to handle signatures roughly 40x larger than ECDSA, and cryptographic agility via OpenSSL 3.x providers or PKCS#11.

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