Quantum Key Distribution
Simulating the BB84 quantum cryptography protocol — the same technology behind a May 2026 breakthrough achieving stable quantum encryption across 120 km of optical fiber. Toggle the eavesdropper to see how quantum physics detects it.
↕ basis rectilinear, bit 0↔ basis rectilinear, bit 1↗ basis diagonal, bit 0↘ basis diagonal, bit 1
Channel is clear — QBER should be near zero
Photons Sent
0
Matching Bases
0
QBER
0.0%
Secure Key Bits
0
Secure Key — matching bases, error-free bits
— waiting for matching bases —
Last 20 Qubits Exchanged
| Alice bit | Alice basis | Bob basis | Bob read | Bases match | Result |
|---|
BB84 Protocol Flow
Quantum Cryptography · cycles every 5s
120 km Milestone
In May 2026, scientists demonstrated stable quantum encryption across 120 kilometers of optical fiber — the farthest coherent quantum key exchange ever achieved over a deployed network.