Secure High-Speed Communication based on Quantum Key Distribution
Today’s information society relies heavily on storing and transferring data in digital form. Cryptography provides the means that is necessary to exchange data securely. It relies on two fundamental parts: first, one needs a secret key, which is subsequently used to encrypt the data with a mathematical algorithm. Secret keys can be transmitted using a trusted messenger, or in a more convenient way, using public key infrastructure, the security of which is based on computational complexity and suffers from the lack of a mathematical proof for the class of complexity. Modern encryption, using algorithms like the Advanced Encryption Standard, is generally considered unbreakable, provided the keys are sufficiently long. However, absolute security can only be guaranteed by the so-called one-time-pad (OTP), where secret keys as long as the message, have to be used.