ISA-95 system boundaries are the functional boundaries used to separate enterprise systems, manufacturing operations systems, and control systems in the ISA-95 model. They help define which system is responsible for which activities, data, and decisions in an industrial environment.
In manufacturing, these boundaries are commonly used when mapping integrations between systems such as ERP, MES or MOM, SCADA, historians, and PLCs. For example, an ERP system may own business planning and order data, an MES may manage production execution and traceability, and control systems may manage real-time equipment control.
ISA-95 boundaries are conceptual and functional. They are not the same as physical network boundaries, cybersecurity zones, or vendor product categories, although they may inform those designs. The term is most often used in data modeling, interface design, responsibility mapping, and ERP-MES-control system integration.