Testing the First Hungarian CV-QKD System on a Real Optical Line

Secure communication is becoming increasingly important as the computing power of quantum computers grows. For some of today’s most widely used classical encryption methods, there is a quantum algorithm that can be used to crack them efficiently. It is therefore very important to be prepared for attackers who have such powerful quantum computers. One possible solution is the One-Time Pad symmetric-key encryption scheme, which requires both communicating parties to have the same key to work effectively. This is achieved in a secure and scalable way by quantum key distribution (QKD). The underlying quantum-mechanical phenomenona guarantee that the parties can detect an eavesdropper and therefore generate a key, that is only known to them. In this paper we present the first Hungarian continuous variable quantum key distribution (CVQKD) system and its first test results, carried out on an optical line of a telecommunication operator. This is the first step towards providing QKD as a service in the future.