Encryption in popular use today is generally based on complex mathematical procedures, which although difficult to break, can be defeated provided you have enough computing power or time to do so. A computer network which makes use of quantum encryption has now been unveiled in Vienna. Quantum encryption technology is 'unbreakable' as it is based on the Heisenberg Uncertainty Principle, which dictates that you can't measure quantum information without disturbing it. What this means in networking terms is that if an outsider attempts to listen in, it is automatically detected by the system and the link is shut down without being compromised. That link can then be re-routed so that secure transmission is not interrupted.