## 2 System Design
### System Architecture Design  
The overall technical architecture of the industrial product quality traceability system is mainly composed of the following parts: the supply chain, data layer, network layer, consensus layer, incentive layer, contract layer, and application layer, as shown in Figure 2. The supply chain layer includes the information system and related data for each link in the preparatory monitoring stage of design and procurement; manufacturing and warehousing in the production practice stage; and sales, logistics, use, maintenance, and decommissioning in the life cycle management stage. The data generated by it are the core data source in this traceability study, which contain important information about the products at different  
Figure 1: Schematic diagram of industrial product information flow system interaction at the manufacturing stage. stages and are crucial for tracing the origin, production, flow, and quality of the products. They are crucial for tracing the source, production, flow, and quality of products. A hash encryption algorithm, timestamps, random numbers, and a transfer mechanism between blocks are used to store the above data in a block data structure in the data layer of the blockchain. The network layer provides the infrastructure for the system to communicate, supports information exchange and data transmission between nodes, and enables effective storage of blockchain data in the nodes through identity and privilege authentication, node management, and discovery, combined with the P2P network protocol. The consensus layer is the crucial part to ensure that all the nodes in the network reach a consensus on the consistency of the data; the practical Byzantine fault tolerance (PBFT) algorithm [26] is used for data resource management, which is not based on proof of interest but a consensus algorithm used in distributed systems that focuses on reaching consistency among nodes that ensures that the consistency of the system can be maintained even if there are node failures or malicious behavior. Its consensus process includes several stages: pre-prepare, prepare, commit, etc. The nodes reach a consensus through mutual communication and message passing. In this process, the concepts of entitlement and resources are not involved, but rather, the consistency and reliability of data are ensured through mutual authentication, message validation, and mutual communication between nodes. The incentive layer is a critical component of the blockchain system. It is used to incentivize participants in the network to perform specific behaviors or provide specific services in order to ensure that they actively participate and maintain the rules of the system. In blockchain, the incentive layer can be used to include token incentives, reward mechanisms, pledge mechanisms, reputation systems, participation rewards, etc. Effective incentives can encourage participants to faithfully and actively participate in the system and ensure its security, reliability, and continuous development. The application layer is the top layer of the blockchain system, providing the interface and functionality for users to interact with the system. In order to realize the function of identification and resolution of industrial product quality traceability systems, as well as the collection and transmission of identification data, it is necessary to establish a metadata template for their identification data. In addition, the identification data can be stored in a distributed manner in the blockchain by adopting the above consensus algorithm, which guarantees their non-comparability and traceability, thus ensuring the trustworthiness and accuracy of the data. In the data storage stage, by associating the acquired data on industrial products at all stages of their full life cycle with corresponding identifiers, data addition and block generation operations within the blockchain are realized by recording the data in the blocks of the blockchain network.