Experimental implementation of secure anonymous protocols on an eight-user quantum key distribution network

Abstract Anonymity in networked communication is vital for many privacy-preserving tasks. Secure key distribution alone insufficient high-security communications. Often, knowing who transmits a message to whom and when must also be kept hidden from an adversary. Here, we experimentally demonstrate five information-theoretically secure anonymity protocols on eight user city-wide quantum network using polarisation entangled photon pairs. At the heart of these anonymous broadcasting, which cryptographic primitive that allows one reveal bit information while keeping their identity anonymous. For n users, retain sender, given no more than − 2 users are colluding. This implementation genuine multi-user beyond standard QKD. Our enhance functionality any fully-connected Quantum Key Distribution without trusted nodes.