Quantum cryptography: How to beat the code breakers using quantum mechanics

In a series of recent experiments a radical new technique has been demonstrated that could have far-reaching consequences for the way in which the confidentiality and integrity of our networks is protected. This technique, known as quantum cryptography, is the result of a synthesis of ideas from fundamental quantum physics and classical encryption and has lead to a radical new approach to the business of secure communications. We review the origins of and developments in this rapidly growing field and assess the current status of both the theory and the experiments.