Abstract:Differences in geographic location and environmental factors lead to differences in rice quality. Rice of high quality origin has excellent quality and taste and is more attractive to consumers, so it is important to study the origin traceability of rice and establish a credible traceability system of rice origin. The traditional IoT blockchain traceability system uploads traceability data to a centralized server, which in turn uploads it to the blockchain;this does not make good use of the resources in the edge nodes and also makes it vulnerable to security risks such as data forgery or data loss. A set of rice origin traceability model was designed based on blockchain and edge computing. The edge layer of this model divided the local blockchain network according to the origin latitude and longitude, each origin region chain contained multiple edge nodes and one core node, and relied on the edge computing capability of embedded devices for real-time data fusion of sensor data and deployment of blockchain on embedded devices. Edge computing ensured the authenticity of the data source, and the blockchain ensured that the on-chain data cannot be tampered, and the combination of the two realized the trusted storage of traceability system data. In addition, the storage scaling method of the blockchain network under the edge computing scenario and edge computing workflow were designed. Finally, after testing and analysis, the average time for querying public traceability data was 45.84ms, the average time for querying private traceability data was 50.92ms, the average time for encrypting onchain of edge nodes was 1.27s, and the storage capacity consumption of edge multi-chain was 18% of that of traditional single-chain, which can meet the practical application requirements of rice origin traceability.