Quantum cryptography was invented about twenty years ago and complements conventional cryptographic techniques to raise security of data transmission over optical fibre links to an unprecedented level. It exploits the laws of quantum physics to reveal the interception of the information exchanged between two stations. According to the Heisenberg Uncertainty Principle, it is not possible to observe a quantum object without modifying it. In quantum cryptography, single light particles – also known as a photons – which are described by the laws of quantum physics, are used to carry information over an optical fibre cable. By checking for the presence of disturbance, it is possible to verify if a transmission has been intercepted or not. Because of this, quantum cryptography was identified in 2002 by the MIT Technology Review and by the Newsweek magazine as one of the ten technologies that will change the world.


This technology can be used to exchange keys between two remote sites connected by an optical fibre cable, and to confirm their secrecy. The keys are then used with secret key algorithms to securely encrypt information. With such an approach it is possible to guarantee future-proof data confidentiality based on the laws of quantum physics. Its deployment on critical links allows thus to raise the information security level of an organization.