The NSA/CSS Quantum CryptoKids® America’s Fuure Codemakers & Codebreakers
Essentially, quantum cryptography is based on the usage of individual particles/waves of light (photon) and their intrinsic quantum properties qubit to develop an unbreakable cryptosystem – essentially because it is impossible to measure the quantum state of any system without disturbing that system. It is theoretically possible that other particles could be used, but photons offer all the necessary qualities needed, their behavior is comparatively well-understood, and they are the information carriers in optical fiber cables, the most promising medium for extremely high-bandwidth communications.
How It Works in Theory
In theory, quantum cryptography works in the following manner (this view is the “classical” model developed by Bennett and Brassard in 1984 – some other models do exist):