FUNCTIONAL MODELING AND ALGORITHMIZATION OF PROCESSES FOR ENSURING CYBER RESILIENCE OF AUTOMATED DISPENSING SYSTEMS FOR PERSONAL PROTECTIVE EQUIPMENT

Abstract

The article addresses the urgent scientific and practical problem of ensuring cyber resilience and operational continuity of automated personal protective equipment (PPE) dispensing systems under destructive cyber impacts. In the Industry 4.0 era, digitalization covers critical occupational safety processes; however, the increasing reliance on network stability creates significant risks of blocking access to protective equipment during cyber incidents. The study provides a comprehensive analysis of the vulnerabilities inherent in classic centralized Industrial Internet of Things (IIoT) architectures. These systems are characterized by a critical reliance on server infrastructure availability and susceptibility to "functional paralysis" during Denial-of-Service (DoS) attacks. Specifically, the limitations of traditional Fail-Secure approaches are highlighted, as they are unacceptable for critical occupational safety infrastructure where the physical availability of resources is the priority, rather than access blocking. The methodological basis of the research is functional modeling of business processes using the IDEF0 standard. This approach allowed for the decomposition of the emergency management process and the identification of critical vulnerabilities at the transaction commitment stage. To address these issues, a hybrid architecture and algorithmic support based on Edge Computing technology are proposed. This enables the decentralization of decision-making logic and transfers the access rights validation process directly to the endpoint level. The developed adaptive cyber resilience algorithm is implemented based on a three-state Finite State Machine (FSM): normal operation (ONLINE), transitional mode (DEGRADED), and emergency mode (OFFLINE). To protect the integrity of offline transactions and prevent data falsification in an isolated environment, a mechanism of cryptographic record encapsulation using hash chaining technology based on the SHA-256 algorithm is applied. Simulation results, conducted using Python, confirm the approach's effectiveness. The experiments demonstrated that under conditions of a prolonged DoS attack, the proposed system ensures a service availability rate of over 98%, whereas the classic architecture demonstrates a complete cessation of service. Furthermore, the effectiveness of the implemented batch data synchronization protocol, which prevents network overload during the connection recovery phase, was proven.