Design And Optimization Of Blockchain Network Layer Data Trandmission Strategy Based On NDN

With the advent of the era of value interconnection,blockchain,as a key technology for building value-delivery network,has been widely used in many fields such as finance,law,energy,healthcare,insurance,and public services.However,the performance bottleneck of blockchain is still an important issue that needs to be solved urgently and it also limits the further development of blockchain technology in emerging fields such as Metaverse,Web 3.0 and Industrial Internet.As a huge distributed system,blockchain is built on the foundation of the underlying TCP/IP network.This leads to a large amount of synchronization of block data and transaction data between nodes,which is one of the important reasons restricting the efficiency of blockchain.However,the research on data transmission strategy for the blockchain network layer is still blank at present.With the gradual maturity of new future network architectures such as Named Data Networking(NDN),the feasibility and value of performance optimization at blockchain network layer are constantly increasing.The NDN network replaces the IP address in the traditional network with the content name,and has the ability of multi-path forwarding and caching,which can greatly improve the efficiency of content distribution.On the one hand,it can accelerate the data transmission of blockchain and improve the throughput of the system;on the other hand,it can also decrease redundant traffic and reduce the huge traffic pressure on the network infrastructure caused by the data synchronization of blockchain.Therefore,to aim at the problems of low data transmission efficiency and high consumption of network resources in the blockchain network layer,this thesis conducts in-depth research on data transmission strategies.The network layer data transmission of blockchain is enabled by Named Data Networking,and the transmission strategy is designed based on NDN to optimize routing forwarding mechanism and caching mechanism,which can improve transaction throughput and guarantee the quality of blockchain services.Firstly,this thesis conducts theoretical analysis and research:a blockchain network layer communication model is proposed,the necessary analysis of the advantages and feasibility of NDN-enabled blockchain network layer is made,and the current research related to the combination of NDN network technology and blockchain is summarized.Secondly,on the basis of these theoretical studies,this thesis designs and optimizes routing forwarding strategies and caching strategies respectively,the research results are as follows:(1)To address the problem of duplication of a large number of P2P data transmission paths between blockchain nodes,and the problem of high computational cost and processing delay caused by the establishment of connections at the application layer,this thesis optimizes the routing forwarding strategy,and proposes a blockchain data transmission structure.This structure establishes data distribution channels among blockchain nodes,realizes routing forwarding of specific paths through the table structure of NDN routers and actively pushes data.It also enables fast transmission by using the multi-path forwarding feature of NDN.Besides,this thesis designs the establishment,use,dynamic maintenance and cancellation methods of the structure,and gives the processing algorithm of the router to implement this transmission structure.The simulation results show that this method can accelerate the block data and transaction data broadcast within the blockchain system.It brings significant improvements in metrics such as the block synchronization time in the whole network and the network traffic consumed in the synchronization process,and greatly decrease the redundant traffic that needs to be handled by network devices.(2)To address the problem of massive redundancy of data transmission in the communication between blockchain nodes,low network caching efficiency,and the waste of cache space,this thesis proposes a blockchain-oriented collaborative caching strategy.This strategy uses K-medoids algorithm to establish collaborative clusters,and proposes a novel "Goblet Pyramid" collaborative caching mechanism within the cluster,which enables nodes to quickly acquire block data and improves the caching performance of the network.This thesis establishes a mathematical model of the optimization problem and gives the iterative solution process,determines the number of collaborative clusters and the initial collaborative cluster centers under the blockchain network topology,and designs the cache space structure and processing algorithm of the router.The simulation results verify the advantages of this caching scheme.Compared with existing typical caching schemes,this strategy reduces the block fetching delay and the network traffic generated by block acquisition,improves communication efficiency of the network layer in blockchain system,and significantly promotes the in-network cache utilization.