"Secure Cryptography with Real-World Devices Is Now a Realistic Possibility"
A new study published in Nature describes how an international team of researchers experimentally implemented a type of quantum cryptography thought to be the 'ultimate,' 'bug-proof' means of communication for the first time. In an experiment based on three decades of fundamental research, the Department of Physics at the University of Oxford demonstrated a complete Quantum Key Distribution (QKD) protocol immune to the vulnerabilities and defects of physical devices that impact current quantum protocols, with theoretical contributions from ETH Zurich, EPFL, the University of Geneva in Switzerland, and the French Alternative Energies and Atomic Energy Commission (CEA). The experiment demonstrates a much higher level of security than is currently possible with traditional computers. Existing QKD implementations rely on communication between 'trusted' quantum devices (and so offers the potential for quantum hacking). The newly demonstrated approach enables secure communication between devices without requiring extensive knowledge of them. This significant breakthrough paves the way for secure cryptography for real-world devices, as well as further quantum information applications based on the device independence principle. The multidisciplinary research team, which included physicists and computer scientists, carried out the successful experiment using 'high-quality quantum entanglement,' an exclusive relationship between two particles that can span vast distances (even light-years) in space while still operating in tandem. Such connections provide greater security and privacy guarantees for communication and financial transactions without the interference of third parties. Currently, secure cryptographic communication is based on traditional computers' inability to calculate prime factors of large numbers. Future quantum computers, however, will be able to easily solve these problems as technology advances, rendering current cryptographic protocols obsolete. This article continues to discuss the QKD protocol demonstrated by the team that is considered to be bug-proof.