Quantum Key Distribution simulation on a distributed infrastructure

Nowadays, the secure communication problem represents one of the main challenges cryptography faces. It consists of providing a way for two distant parties to privately communicate over a shared channel, even in presence of an eavesdropper. Arguably, the One-time-pad (OTP) could represent a perfect cypher that will allow solving the aforementioned problem providing a way to achieve perfectly secure communication. However, for the OTP scheme to be applicable, the two communicating parties need to establish a shared key and each to have their copy; achieving such a purpose while an eavesdropper is present on the channel represents a whole new problem: the key distribution problem. Currently, the main way of dealing with such a challenge is using public-key cryptosystems. Nevertheless, the security proof of these systems is entirely based on the computational complexity of the mathematical operations they are based on. Consequently, they are vulnerable to unanticipated advances in hardware and software like quantum computers for example. As a result, in 2015, the US National Security Agency (NSA) announced a plan for transition to quantum-safe cryptosystems. Broadly speaking, two different approaches have been developed: Post-Quantum Cryptography and Quantum Cryptography. The former aims to develop new public-key encryption schemes that are safe against known quantum attacks. It has the advantages of being compatible with the current crypto infrastructure but, there will always be the possibility for new attacks to be developed that would break these schemes. The latter aims to leverage the law of quantum physics to provide security that will remain independent of all future advances of computational power. Quantum Key Distribution is the branch of Quantum Cryptography devoted to addressing the key distribution problem in a quantum-safe way. Being a cutting-edge discipline, its deployment in the real world still isn’t easy or cheap and that is exactly why the interest in the simulation of QKD has thrived. This thesis proposes a new solution to simulate QKD that users can easily insert inside their distributed infrastructure and use for evaluating the performance of different QKD protocols.