UltimaOS uses NIST-standardized lattice cryptography for every public-key operation, paired with classical symmetric primitives that are themselves believed to be quantum-resistant. The result is a hybrid stack where no single algorithm failure compromises the system.
01
ML-KEM-768 for key exchange
Fresh 256-bit symmetric session keys are encapsulated with ML-KEM-768 (FIPS 203) for every new conversation, file share, and call. The resulting shared secret seeds a symmetric session encrypted with XChaCha20-Poly1305.
02
ML-DSA-65 for signatures
Account identities, invitations, device enrollments, and signed audit records use ML-DSA-65 (FIPS 204). Signatures are 1,959 bytes — larger than ECDSA but acceptable for an interactive workspace.
03
XChaCha20-Poly1305 for payloads
All content — messages, files, calendar events, AI conversations — is encrypted with XChaCha20-Poly1305, an authenticated symmetric cipher. Symmetric primitives with 256-bit keys have no known quantum speedup beyond Grover's bound.
04
Hash-based backup for software updates
Software updates are signed with a hash-based signature scheme (SLH-DSA / FIPS 205) as a second layer of insurance. If a flaw is ever discovered in lattice signatures, the update channel remains verifiable.