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    CALCULATORiQ™
    Quantum Cryptography

    BB84 Protocol Lab

    Experience quantum key distribution. Generate unbreakable encryption keys and detect eavesdroppers!

    BB84 Protocol Steps

    Eve (Eavesdropper)
    Generate Bits
    Choose Bases
    Transmit Qubits
    Measure
    Compare Bases
    Extract Key

    Understanding BB84 Protocol

    How It Works

    Alice encodes bits in quantum states using two bases: rectilinear (+) and diagonal (×). Bob measures with randomly chosen bases. When bases match, they get the same result.

    Detecting Eavesdroppers

    An eavesdropper (Eve) must measure qubits to read them, disturbing the quantum state. This causes errors that Alice and Bob can detect by comparing a subset of their key.

    Why It's Secure

    The no-cloning theorem prevents Eve from copying quantum states. Any interception inevitably introduces detectable errors above the 11% threshold.

    Real-World Use

    BB84 is commercially deployed in high-security applications. Banks, governments, and data centers use QKD for truly unbreakable encryption keys.