Public key cryptography has raised cryptography from a curiosity, useful mainly to governments, to its status as a pillar for modern communications. But above this magnificent throne hangs a sword of Damocles in the form of quantum computing, motivating the development of new approaches.
Some have turned to physics, developing systems with security guarantees based on natural laws. The most popular is Quantum Key Distribution, but its complexity has spurred the development of alternatives.
We examine KKD, an entirely electronic system, charting the attacks and countermeasures that have been introduced since its introduction in 2006.