Security Guide · Cryptographic Resilience
A large enough quantum computer will break the public-key cryptography the internet runs on today. The algorithms to replace it are now standardised — the real work is migration. This is the problem in plain terms, and how the entityOS closed-internet architecture is built to absorb it.
A cryptographically-relevant quantum computer running Shor's algorithm can factor and solve discrete logs efficiently — collapsing RSA, Diffie-Hellman and elliptic-curve keys. No bug, no patch: the hard problem simply stops being hard.
Adversaries record encrypted traffic today and hold it to decrypt once the hardware matures — “harvest now, decrypt later.” Anything with a long confidentiality life is at risk in the present tense, not on some future Q-Day.
NIST finalised its first post-quantum standards in August 2024. The unknown is no longer which algorithm — it is whether your architecture can migrate to it in time, and whether it was designed to migrate at all.
The question is no longer “is quantum real?” It is “can what I built move?”
Two quantum algorithms threaten today's cryptography, and they threaten it very differently. Understanding which is which decides where migration effort actually goes.
Public-key cryptography is broken outright. What protects nearly every key exchange and signature on the internet today simply falls.
Only a quadratic speed-up against symmetric ciphers and hashes. Doubling the key size restores the margin — and hashes are the foundation of what comes next.
“Harvest now, decrypt later” moves the deadline forward. Data intercepted today — medical records, credentials, contracts, anything with a confidentiality life beyond ~2030 — can be banked now and opened the day the hardware arrives. For long-lived secrets, waiting for Q-Day is already too late.
After an eight-year process, NIST published the first post-quantum standards on 13 August 2024. They are not interchangeable — each replaces a specific job classical crypto does today.
Module-lattice key encapsulation (from CRYSTALS-Kyber). The primary tool for key establishment — the direct replacement for RSA and ECDH in a TLS handshake.
Module-lattice digital signatures (from CRYSTALS-Dilithium). NIST's default signature scheme — the replacement for RSA-PSS and ECDSA in certificates and code signing.
Stateless hash-based signatures (from SPHINCS+). Slower and larger, but resting on a different mathematical foundation — insurance against a break in the lattice family.
FN-DSA (Falcon) adds compact lattice signatures; HQC, selected March 2025, is a code-based backup KEM. Together they give the suite algorithm diversity if any one family weakens.
A June 2026 U.S. executive order and NSA's CNSA 2.0 set the migration horizon. The dates below are the planning reality — and they assume you can find and move every use of vulnerable crypto in your estate first.
CNSA 2.0: post-quantum required for new national-security systems.
Federal Commerce post-quantum migration pilot.
Key-establishment migration; RSA & ECC deprecated for new systems.
Digital-signature migration deadline for federal civilian systems.
RSA & ECC disallowed entirely, including legacy interoperability.
Hybrid X25519 + ML-KEM handshakes already ship in Chrome, Cloudflare, AWS and Google — the migration is underway, not theoretical.
Not every primitive is in danger, and not every fix is the same. This is the honest picture of what a quantum adversary reaches — and the entityOS path for each.
| Primitive | Role today | Under a quantum adversary | entityOS path |
|---|---|---|---|
| RSA-2048 | Key exchange & signatures | Broken (Shor) | Hybrid ML-KEM at transport |
| ECDH / ECDSA | TLS handshake & signatures | Broken (Shor) | Hybrid ML-KEM · ML-DSA |
| AES-256 | Bulk data encryption | Safe (~128-bit) | Retained |
| SHA-256 / 384 | Hashing & digests | Safe, margin intact | Core of KERI pre-rotation |
| KERI pre-rotation | Identity key rotation & recovery | PQ by construction | Stage 3 — SSI (KERI / ACDC) |
The signing keys themselves still migrate to post-quantum signature suites. What pre-rotation protects is the rotation and recovery mechanism — so a break in a live key can never seize the identity.
entityOS is not a new cipher. It is a layered, crypto-agile architecture — each stage independently reduces exposure and can adopt NIST post-quantum primitives as they land.
The layered design is the point. Each stage migrates on its own timeline — network, transport, then identity — so adopting ML-KEM, ML-DSA or their successors never means rebuilding the platform.
Closing the public edge cuts how much encrypted traffic an adversary can record now to break later — the harvest-now-decrypt-later threat is reduced before any algorithm changes.
Because trust is enforced in layers, each can swap to a post-quantum primitive independently. Adopting NIST FIPS 203 / 204 / 205 is a configuration path, not a re-architecture.
KERI pre-rotation protects the identity's control and recovery with one-way hashes, so a compromised live key — even to a quantum attacker — can never seize the identifier.
The post-quantum transition is not a single switch on a future date. It is inventory, then layered, staged migration — and it starts the moment your data has a confidentiality life longer than the hardware timeline.
entityOS is built for exactly that: a closed-internet edge that shrinks what can be harvested, a crypto-agile transport ready for hybrid ML-KEM, and a KERI identity layer that is post-quantum resilient by construction.