qkd
2 free lessons tagged qkd across Science. Each one is a short sequence of focused steps with narration and a five-question quiz at the end — take them in any order, no signup required.
Why Nobody Deploys It: The Gap Between Proof and Product
QKD has an unconditional security proof and almost no deployment. This lesson covers the authentication bootstrap it cannot solve, distance limits and the trusted node compromise, attacks on real hardware that the proof does not cover, why NSA and NCSC recommend against it, and where quantum genuinely delivers.
Quantum Key Distribution: BB84 and Why Eavesdropping Shows
Quantum cryptography uses physics rather than computational hardness. This lesson covers the no-cloning theorem, the BB84 protocol step by step, why measurement in the wrong basis leaves a detectable trace, the error rate threshold, and the entanglement-based alternative.