Quantum Key Distribution Eavesdrop Lab | Interactive BB84 Network Simulator

Core Quantum Internet Principle: Quantum networks do not exceed the speed of light or replace classical optical bandwidth. Their physical superiority lies in the No-Cloning Theorem and Heisenberg Uncertainty: any eavesdropper (Eve) attempting to measure unknown photon polarization bases collapses the quantum state. Eve's inevitable basis errors inject a 25% disturbance into matched-basis photons, driving the Quantum Bit Error Rate (QBER) far beyond the cryptographically secure 11% threshold.

Live BB84 Optical Fiber Transmission Bench Speed: 1x

Pulses Emitted

Eve Intercepts

Sifted Key (Bits)

Bit Errors

Current QBER

0.00%

Raw Secret Key

0 bps

Alice Basis Mode

Bob Basis Mode

Eve Intercept Probe 50%

Fiber Loss & Dark Noise 2.0%

BB84 Basis Reconciliation & Sifting Ledger Real-time Photon State Collapse Logs

#	Alice Bit/Basis	Polarization	Eve Intercept	Bob Basis	Bob Bit	Bases Match?	Status

Cryptographic Security Evaluation

QBER vs 11.0% Abort Threshold 0.0%

0% Clean 11% Max Threshold 30%+ Intrusive

Reconciliation Math: When Alice and Bob choose matching bases, bit values agree with 100% fidelity on clean fibers.

When Eve intercepts with random bases, Bob experiences a 25% error rate on those sifted bits. If total QBER exceeds 11%, privacy amplification fails and the key is safely aborted.

Optical Channel Presets

Polarization Legend (BB84)

+ Rectilinear: Bit 0 = 0° (↑), Bit 1 = 90° (→) +

× Diagonal: Bit 0 = 45° (↗), Bit 1 = 135° (↘) ×