Two-Tier Trust Structure Model for Dynamic Supply Chain Formulation

With the ongoing development of DX, the linkage between physical and cyber environments is expanding and is increasingly being applied to business aspects such as supply chains. At the same time, cyber-attacks are becoming more diversified, and information security is becoming more and more important. The Information Security White Paper 2019 reported that one of the most pressing issues in the supply chain is that the scope of responsibility between the contractor and subcontractor is unclear. In this paper, we propose a two-tier trust structure model featuring inter-organizational security policy matching for dynamic supply chains that recombines subcontractors for each contract. The proposed structure consists of a trust model at the contractor side and a zero-trust model between the contractor and the subcontractor. The results of qualitative evaluation show that this two-tier model can help clarify the scope of responsibility in dynamic supply chains.