Secure the future with quantum physics.
From the BB84 protocol to quantum networks and post-quantum signatures: an interactive reference built from your notes and completed with everything a full course would cover.
Six ideas that define the field.
Each slide links to the page that develops it.
Use the arrow keys to move between slides.
Ten topics,
one complete picture.
Quantum foundations for cryptography
The physics that makes quantum cryptography work: qubits, measurement, no-cloning, entanglement, Bell tests, entropy and the quant…
02 / TOPICClassical cryptography and the quantum threat
How RSA, Diffie–Hellman and elliptic curves work, why Shor’s algorithm breaks them, what Grover does to symmetric ciphers, and why…
03 / TOPICQuantum key distribution protocols
BB84, B92, six-state, SARG04, E91/BBM92, COW, DPS, continuous-variable, MDI, twin-field, device-independent and more, with worked …
04 / TOPICSecurity of QKD: attacks, proofs and post-processing
What “unconditional security” means, the assumptions behind it, decoy states, finite-key and composable security, error correction…
05 / TOPICPhotonic hardware: beam splitters, sources, detectors and channels
Beam-splitter quantum optics and the Hong–Ou–Mandel effect, photon sources, single-photon detectors, fibre and free-space channels…
06 / TOPICQKD networks: architectures, routing and deployments
Point-to-point links, trusted-relay and optical-switched networks, key management, physical-layer key-rate models, resource alloca…
07 / TOPICQuantum communication: teleportation, entanglement distribution and the quantum internet
Superdense coding, teleportation, entanglement swapping and purification, quantum repeaters and memories, the PLOB bound, free-spa…
08 / TOPICBeyond QKD: other quantum cryptographic tasks
Quantum random numbers, secret sharing, digital signatures, bit commitment and the no-go theorems, coin flipping, oblivious transf…
09 / TOPICPost-quantum cryptography and ML-DSA
Quantum-resistant classical cryptography: the NIST standards (ML-KEM, ML-DSA, SLH-DSA, FN-DSA, HQC), lattice mathematics, a detail…
10 / TOPICStandards, applications and outlook
Where quantum communication and cryptography are used, who standardises them, what the limits are and what to expect next.…
In one line
Quantum key distribution gets its security from physics; post-quantum cryptography gets it from hard mathematical problems.A migration plan usually needs both ideas. See how they fit together ↗
Four stages of understanding.
Qubits, no-cloning, entanglement, entropy, and the classical threat from Shor and Grover.
BB84, E91, MDI, twin-field, decoy states, post-processing and attacks.
Photonic hardware, QKD networks, teleportation, repeaters and satellites.
Post-quantum standards, ML-DSA, hybrids and how QKD and PQC fit together.