Browsing by Subject "quantum key distribution"

Secure data transmissions are crucial part of modern cloud services and data infrastructures. Securing communication channel for data transmission is possible if communicating parties can securely exchange a secret key. Secret key is used in a symmetric encryption algorithm to encrypt digital data that is transmitted over an unprotected channel. Quantum key distribution is a method that communicating parties can use to securely share a secret cryptographic key with each other. Security of quantum key distribution requires that the communicating parties are able to ensure the authenticity and integrity of messages they exchange on the classical channel during the protocol. For this purpose they use cryptographic authentication techniques such as digital signatures or message authentication codes. Development of quantum computers affects how traditional authentication solutions can be used in the future. For example, traditional digital signature algorithms will become vulnerable if quantum computer is used to solve the underlying mathematical problems. Authentication solutions used in the quantum key distribution should be safe even against adversaries with a quantum computer to ensure the security of the protocol. This master’s thesis studies quantum safe authentication methods that could be used with quantum key distribution. Two different quantum safe authentication methods were implemented for quantum key distribution protocol BB84. The implemented authentication methods are compared based on their speed and size of the authenticated messages. Security aspects related to the authentication are also evaluated. Results show that both authentication methods are suitable to be used in quantum key distribution. Results also show that the implemented method that uses message authentication codes is faster than the method using digital signatures.