A Quantum Routing Model and Protocol Suitable for User Private Networks

Quantum Key Distribution (QKD) can achieve the secure distribution of keys among multiple users. By leveraging quantum bits for information interaction and transmission, theoretically, the quantum key distribution network is a method of confidential communication with unconditional security. In recent years, many researchers have been attempting to build small-scale quantum key distribution networks. However, the routing protocols in these small-scale networks are all designed for local quantum key distribution, while the practical research on wide-area quantum key distribution networks is relatively scarce, especially the lack of effective routing algorithms for key transmission. Wide-area quantum key distribution networks are characterized by a large number of nodes, large scale, and complex connection relationships, which lead to problems such as complex routing management and high node load pressure. To address this issue, this paper proposes a cross-domain routing model suitable for wide-area quantum key distribution networks, taking cross-domain user private networks on wide-area networks as the research object, and puts forward the concepts of “Interface” and “Link”. On this basis, based on a randomly constructed quantum user network, a novel link state advertisement method and a flooding mechanism are designed, and an inter-domain routing protocol for quantum keys and a key distribution method are provided. Based on this cross-domain model, automated routing management can be carried out, crossdomain quantum key transmission in user private networks can be achieved, and the key problems in the process of quantum key distribution can be effectively solved.