Welcome to the sixth QGT! Learning more about Quantum Key Distribution Protocols has never been so easy.
This App focuses on BB84 protocol and Ekert91 protocol. In BB84, the information is codified on the photon polarization, so the receiver must use birefringent crystals to measure the photon. If Alice (emitter) and Bob (receiver) choose the same basis, they measure the same value. Ekert91 is a variant of BB84 that uses EPR entangled states that are generated by an external source. In this case, if Alice and Bob select the same basis, they measure opposite values.
In both protocols, if an evaversdropper (Eve) tries to measure the photons on the fiber, the correlation of the information between Alice and Bob can be broken allowing them to detect somebody else was measuring.
I hope you enjoy this App and learn more about quantum cryptography.
David