Research On Traceability Strategies Of Supply Chain Systems Based On Blockchain Technology

In the traditional supply chain systems,there are many phenomena,such as information islands,untimely interaction of each link,and the authenticity of products is difficult to guarantee.With the maturity of 5G,Internet of Things and other technologies,the competitive markets once again show the advantages of "Internet of Everything".Using the Io T technology to manage supply chains is one of the important means to improve the efficiency of markets supervision.However,most supply chain systems use clustered servers to store transaction data.If an illegal attack occurs,data leakage and other vicious events will damage the interests of participants in the supply chains.And most systems use RFID coding to achieve traceability requirements,and coding methods are prone to problems such as loops,encoding overflow,etc.To this end,The system introduces a distributed blockchain architecture with decentralized,traceable,and anti-tampering characteristics a distributed blockchains which the characteristics of decentralization,traceability and immutability.And system uses RFID to collect product data to improve transaction transparency and traceability efficiency.This paper analyzes supply chains traceability requirements and divides them into two categories: path traceability and containment relationship traceability.In order to improve the security of the system,the blockchains architecture is introduced to store transaction data.So,this paper proposes a supply chain traceability system model based on blockchain technology,this model uses Io T devices to monitor product transactions in real time way,and stores the data generated in the supply chain into blockchains,which enables information share among cooperative enterprises,improve transaction transparency and avoid the phenomenon of information islands.According to the requirements of path traceability,this paper first analyzes the data needed to realize path traceability,then designs a Merkle Pbitree block storage index structure that supports path traceability query based on the traceability characteristics of blockchains.This structure is a perfect binomial tree that can be encoded.With the encoding method of middle-order traversal,the encoded value of the left subtree in the tree structure is always smaller than the encoded value of the right subtree.Therefore,when using the encoded value to replace the hash value to realize path traceability,it can increase the index speed in the interblocks.And the code interval value and hash value of root node are stored in the blocks header together,thus it can increase the query speed in the intra-blocks.Based on the Merkle Pbi Tree,it designs the query algorithms of forward traceability,backward traceability,process traceability and recall,respectively.The experimental results show that Merkle Pbi Tree has good tracing query efficiency in complex supply chain with massive data.According to the requirements of containment relationship traceability,this paper analyzes the data needed to realize the traceability of containment relationship.If the Merkle Pbi Tree structure is used to trace back,the efficiency is low.Therefore,combined with the geometric vector coding strategy,the containmen relationships in the transaction data are converted into the RFID coding values.This paper studies the tracing requirements of RFID object containment relationships by optimizes the existing geometric vector coding strategy to solve the data collision and data overflow problems.Based on the idea that an infinite number of vectors can be inserted between any two vectors,combined with the relationship between the coordinates of the corresponding points on the concentric circles and the radius,an optimized coding strategy using concentric circles to reduce the vector coordinates is proposed.The feasibility and efficiency of the optimized strategy are discussed in combination with the requirement of containment relationship traceability.The experimental results reveal that the proposed geometric vector coding strategy has better performance in coding initialization,storage overhead,vector update and tracing queries than the existing vector coding strategies.