QuStream · Operational Perfect Secrecy

Encryption you can prove.
Not hope.

The one-time pad is the only cipher Shannon ever proved unbreakable. QuStream is the first system to make it deployable — over any network, on the hardware you already have.

Read the paperDeploy→
Harvest now · decrypt later

The archive is already full.

No one is breaking today’s encryption. They are storing it. When the math gets cheap, the archive opens.

Encrypted bytes captured · worldwide · this hour

247,938,122,483

Decryption horizon · 2029

Google Quantum AI · Jan 2026 · timeline confirmed

Intermission · 1949

“The number of different keys must be at least as great as the number of different messages.”

Claude Shannon · Communication Theory of Secrecy Systems

The industry could not distribute keys at that scale. It built on conjecture instead. Here is the one we solved.

Inside one Q-Block

A small secret pulls a pad from public noise.

The Q-Block is an authenticated public noise epoch. The endpoint's secret DFK ratchet selects bits locally, derives the one-time MEK, and refreshes the next DFK state. No keys are inserted into the block.

Q-Block epoch4,096 bits example
DFK ratchetlocal secret state
MEKderived once, then burned
Claimbounded ITS model
R · 0x000000
front
D700093365671B102F6A9B136BADE0808D157BDB47C541E98F2147AC98CDE06AD6AEA1A7
R · 0x000240
right
FDE75C2502DC27EA18315539B3CB7B9688CD6BC6899B3BCBECD93EEB256C08AAE6776ECA
R · 0x000480
back
255E835115C59B822A914AE118E56533D425FF7B91F66CFDC33A403D1F1750FF97F0AE48
R · 0x0006c0
left
616AB05BF067EABCF90D2E306FBF92BA8622699EB2184860A7C701C55A92AACFFE1E96C4
R · 0x000900
top
074D59282A45C8BD5969F689CA5E37CFF0061F138087831A6D4476E6EBE24CBD6E449923
R · 0x000b40
bottom
AA8D32DA942429E85FAAD5907F05C756A857D4FFCF07118E27B6D147244AA9AE7BE66B87
Reducing the need for trust

No master key. No certificate authority. No trusted middle.

Each endpoint forward-evolves a local DFK state after deriving a one-time MEK from the public noise epoch. Relay nodes see the epoch, counters, and ciphertext, but not the secret ratchet state. Past traffic stays sealed unless the endpoint itself is compromised.

(MEK_t, DFK_t+1) = F(DFK_t, Q_t, ctx_t)
Measured38.2 Gbps · 40G line · 1.2% overhead

What it costs

Bytes, cycles, latency

One XOR per byte. On the hardware you already have.

Thirty-two byte signatures, not twenty-four hundred. Under a cycle per encrypted byte. It fits inside the firmware budget of a smart meter, the power envelope of a drone, and the latency floor of a 400-gigabit optical line.

Benchmarks · published figuresARM Cortex-M4 · Falcon-512 · AES-GCM SW
Signature sizeBytes per signature
QuStream
32 bytes
Falcon-512
2,420 bytes
CPU cost on Cortex-M4Cycles per signing operation
QuStream
~ thousands
Falcon-512
19,400,000
Data-plane throughputCPU cycles per encrypted byte
QuStream
0.9 cpb
AES-GCM (software)
~6.5 cpb

Figures from NIST PQC round-3 submissions and published benchmarks. QuStream numbers assume a local DFK ratchet, authenticated public noise epochs, and MAC-based integrity protection.

Fits the firmware budget of a smart meter100G · 400G · 800G line-rate

The horizon is 2029

The paper is peer-reviewed.
The silicon is already running.
The archive doesn’t wait.

01 · Read

The Springer paper

FTC 2025 · Chapter 17

Open→

02 · Explore

The platform

Q-Stream · DFK · Q-Block

Open→

03 · Deploy

Talk to the team

Enterprise · defence · infrastructure

Open→
QuStreamOxford · United Kingdom
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