Application Technology Research On Large-scale Quantum Key Distribution Network

Quantum Key Distribution(QKD)technology is based on the Heisenberg uncertainty principle,unknown quantum state can not be cloned principle and quantum state measurement of collapse and other basic principles of quantum mechanics,can provide both the absolute security of the communication key.After C.H.Bennett and G.Brassard proposed the first quantum key distribution protocol BB84 protocol,quantum key distribution has been progressing both theoretically and experimentally,and has become the first quantum information technology to be applied in practical applications.The point-to-point feature allows the quantum key distribution system to communicate only between the nodes and the nodes.From the practical application,the quantum key distribution must be transmitted from the point-to-point to the quantum key distribution network.Because the quantum key distribution network is divided into two categories because of the limitation of the technology,we call the wide area network which needs the relay node as the backbone network,and the LAN / MAN that does not need to be relayed and use the classical optical device is called Access Network.The quantum key distribution backbone network mainly implements the forwarding function of the security keys between the remote nodes and the multi-nodes.The quantum key distribution access network mainly implements the multi-user dynamic access function in the metropolitan area.In this paper,we analyze the difficulties in the application of large-scale quantum key distribution network from research to practical application,and propose the corresponding solutions.First,in order to solve the problems encountered in the application of the backbone network,this paper analyzes the limitations of the network layer protocol in the existing QKD network based on the trusted relay quantum key distribution network architecture.Combining with the latest development of the classical computer network,The software defines the concept of a quantum key distribution network(SDQKDN).In this paper,the architecture of SDQKDN is discussed,and the topology management and forwarding management of SDQKDN are designed.Based on the existing SDN technology,we built mininet + floodlight experimental environment to simulate the SDQKDN prototype network,and simulated the topology management and forwarding management services in SDQKDN through floodlight topology discovery and static flow table formulation.Secondly,this paper analyzes the implementation schemes of multiple access networks.After considering the factors such as cost,key generation rate,and channel control protocol complexity,the implementation scheme of access network based on optical switch network is selected.In this paper,Q3 P protocol is extended to study the time-division multiplexing mechanism based on optical switch network and the user dynamic access mechanism in order to meet the functional requirements of quantum key distribution access network.Based on the CORE platform,an experimental network is designed to test the extended Q3 P protocol.Finally,the design of the backbone network and the design of the access network are integrated.Taking a single communication process as an example,the paper introduces how the backbone network and the access network work together.The software defines the quantum key distribution network and the extended Q3 P protocol Is how to work together.