A privacy-preserving distributed protocol for secure data sharing in untrusted supply chain.

Modern supply chains require effective information sharing and inter-organizational collaboration while safeguarding sensitive data to ensure operational efficiency. Despite significant progress, existing methods rarely provide a comprehensive approach that simultaneously ensures privacy and visibility, maintains owner control, and supports horizontal and vertical collaboration in distributed environment without reliance on centralized or globally trusted third parties. Most current works rely on centralized management or blockchain-based architectures that introduce issues of scalability, storage, and integration. To address these gaps, this paper presents a hierarchical model for secure data storage, access, and sharing, integrated with a secure protocol that manages authentication, authorization, and distributed access control. The proposed design enables private yet visible information exchange through metadata and hash propagation while preserving confidentiality, integrity, and anonymity. Protocol-level feasibility and security properties are established through formal and informal analysis, including AVISPA-based verification under standard symbolic adversary models. Simulation-based experimental evaluations across multiple network configurations demonstrate that, within the modeled topology and protocol assumptions, scalability is strongly influenced by balanced connectivity among supply chain nodes, resulting in stable throughput and low latency under increasing complexity. Overall, the proposed approach achieves favorable trade-offs between security, functionality, and computational and communication costs compared with existing methods, providing a well-founded architectural and protocol-level basis for secure information sharing in distributed supply chain environments.