Research On Model And Routing Technology In Wide-area Quantum Key Distribution Network

Quantum key distribution technology is known as one of the most subversive cutting-edge technologies within the domain of information security.Along with the research of point-to-point quantum key distribution technology increasingly mature,quantum key distribution network has become the research focus at home and abroad,since it can address the requirements of multi-user,high speed,long distance and networking for secret key distribution.Under the wide-area environment,the increasing of network scale and application demands brings lots of new challenges to the theory and technology research of quantum key distribution network.However,the existing quantum key distribution network model has low distribution efficiency and the existing quantum key distribution network routing mechanisms are relatively simple,which can not address the service performance requirements of the wide-area quantum key distribution network.In order to solve the problem of how to improve the service performance of wide-area quantum key distribution network,this thesis starts from improving the key material utilization rate in key relay.And then the 5 Layers Parallel Distribution model is proposed for wide-area quantum key distribution network.Based on this model,the service capacity measuring method for quantum key distribution network is researched,and an Area-dividing and Hierarchical based Dynamic Routing scheme and its routing protocol and algorithms are designed too.The main works and results are as follows:1.A high distribution efficiency 5 Layers Parallel Distribution model(5LPD)is proposed for quantum key distribution network.Focused on the problem that the existing Single Layer Serial Distribution model(SLSD)has low key material utilization rate in key relay and low distribution efficiency,the key material consumption is analyzed and the 5LPD is proposed based on layering thought,which achieves parallel and pipeline quantum key distribution among each layer.The network topology of "backbone and access network" is introduced for 5LPD.Then the key relationship graph is proposed based on graph theory to describe the key relationship within the 5LPD,which established the theoretical foundation for the follow research.The analysis shows that the 5LPD can increase the key material utilization rate and the key distribution efficiency in large scale quantum key distribution network.2.A service capacity measuring method based on key capability graph is proposed for quantum key distribution network.Focused on the problem of lacking a quantitative method to measure the service capacity of quantum key distribution network,by defining the key capacity graph and building the dynamic process model of key capacity graph,a quantitative measure method is proposed which use the key material and its dynamic change of each link to describe the service capacity of quantum key distribution network.Based on this method,the service capacity of quantum key distribution network under two models of SLSD and 5LPD are measured separately.Then an example quantum key distribution network is used to analyze the service capacity of networks under the above two different models by quantitatively calculation and simulation.The analysis results prove the versatility and validity of the measure method,and also show that the service capacity of quantum key distribution network under 5LPD is obviously higher than SLSD.3.An Area-Dividing and Hierarchical based Dynamic Routing scheme(AHDR)is designed for the key-backbone-exchange layer of the 5LPD quantum key distribution network in wide-area.For the key-backbone-exchange layer of the 5LPD quantum key distribution network,the network scale is still large and the relay path within it is still long.Focused on these above characteristics,the AHDR is designed to ensure the key distribution efficiency.Firstly,the scale constrain criterion and the partition strategy of routing area are proposed to divide the backbone network into multiple small-scale routing areas.Secondly,under the foundation of area-dividing,a routing area derivation mechanism based on topology abstraction is designed,and an area-dividing and hierarchical backbone network is established.At last,the basic idea of achieving the intra-area and inter-area routing through different routing areas in different layers is introduced.The analysis and simulation show that the AHDR can simplify the complexity of routing management in wide-area,reduce the length of relay path and lay the foundation for routing.4.A Quantum key Network routing protocol based on Flooding(F-QNRP)is designed to exchange routing information.Focused on the problems of fast link state change and high efficiency demand of routing information exchange in quantum key distribution network,the routing requirements of quantum key distribution network are analyzed and the F-QNRP is proposed by adopting the thought of modular and compostable.This protocol consists of three modules: Hello exchange,State request and State spread,which can achieve different routing exchange requirements,such as network state collection,fast routing synchronization for newer,network state spreading and so on,by flexibly combining different modules.The analysis shows that the F-QNRP can ensure the routing information exchange timely and coincident.5.The intra-area and inter-area routing algorithms are designed.Focused on the problem that the existing routing algorithm KQ-RA pays more attention to the performance of a single relay path but not the whole network and indirectly wastes the key material,an intra-area Routing Algorithm based on the Shortest Key Replenish Time(SKRT-RA)is proposed.In SKRT-RA,the key replenish time which considered both the current key material and the key generation of a link is proposed and taken as the link weight when calculating the relay path.Then the optimal relay path is calculated by improving the KQ-RA,which can not only ensure key relay transfer but also consume the key material reasonably.Focused on the characteristics of the area-dividing and hierarchical structure in AHDR,an inter-area Routing Algorithm based on Least Routing Area Transfer(LRAT-RA)is proposed.The LRAT-RA takes the SKRT-RA as the foundation and makes full use of the physical nodes shared by different layers' routing areas in to link up the sub-path within different layers.The analysis and simulation show that the LRAT-RA can minimize the routing areas that participate in key relay,and then increase the efficiency of inter-area key relay.