## 5 Blockchain-Based Supply Chain Security Solutions and Integration Models
### Data Privacy with Zero-Knowledge Proof (ZKP) and Confidential Transactions
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Ref.** & **Description** & **Advantages** & **Limitations** \\ \hline \multirow{4}{*}{[87]} & Secure traceability in industrial production using blockchain and ZKP. BeHSCM model enhancing privacy and security in healthcare security, automation. & Privacy, reliability, transparency, collaboration, auditability. & Cost, data reliability, scalability, standardization needs, blockchain security. \\ \cline{2-4}  & & & \\ \cline{2-4}  & & & \\ \cline{2-4}  & & & \\ \cline{2-4}  & & & \\ \cline{2-4}  & & & \\ \cline{2-4}  & & & \\ \hline \hline \end{tabular}
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Table 8: Comparative analysis of zero-knowledge proof studies in blockchain-based supply chains. quently, confidential transactions represent a crucial solution for enhancing commercial confidentiality and data security within blockchain-based supply chain systems [22]. A blockchain-based approach named B-CONFIDENT was proposed to ensure enterprise privacy in blockchain-based supply chains [96]. Using a permissioned blockchain architecture and smart contracts, the approach leverages PrivateFor and ConfidentialFor lists to restrict sensitive data access solely to authorized actors, ensuring transparency while preserving confidential information. Utilizing the GoQuorum platform and the Tessera private transaction manager, the method securely transmits transactions, relying on blockchain-based access controls instead of traditional public-key encryption methods for maintaining data privacy. In SCM applications, especially in multi-stakeholder supply chains, achieving a balance between commercial data privacy and transparency is vital [91; 94]. For example, information, such as pricing policies, special conditions in supply agreements, or quality control reports, needs to be verifiable without compromising confidentiality. Cryptographic approaches like ZKPs and confidential transactions provide trustworthy verification along the supply chain, allowing transactions without disclosing sensitive data to unauthorized parties [87; 93; 95]. Consequently, these methods protect competitive commercial secrets while ensuring regulatory compliance and internal trust. Ultimately, these cryptographic techniques not only enhance data security but also facilitate privacy-oriented designs within the digital transformation of SCM processes [86; 90]. Cross-Chain Supply Chain Management Systems: Interoperability, Security Risks, and Architectural Design  
In blockchain-based supply chain systems, interoperability is critically important for secure data and asset transfers between different blockchain networks [97]. Today, supply chains often involve blockchain solutions provided by various platforms, making cross-chain transactions inevitable [98]. For instance, a supplier might maintain records on a permissioned blockchain network based on Hyperledger Fabric, while a distributor or financial institution operates on a permissionless blockchain, such as Ethereum. Ensuring secure data and asset transfers between these systems is essential for maintaining supply chain integrity. However, interactions across different blockchain networks introduce vulnerabilities to cross-chain attacks, complicating the maintenance of fundamental security principles such as data integrity, authentication, and authorization. Blockchain bridges are among the most prevalent applications facilitating cross-chain transactions. These bridges consist of smart contract mechanisms designed to transfer assets or data between two or more chains. However, these bridges can represent single points of failure and become attractive targets for attackers. Malicious actors can exploit vulnerabilities in bridge-based smart contracts, enabling unauthorized asset transfers or the manipulation of cross-chain transaction verification processes. Particularly, centralized or semi-centralized bridges are susceptible to large-scale security breaches.