In a 2-tier ERP scenario, you can use two integration technologies to integrate the headquarters of a company running on SAP S/4HANA with a subsidiary running on SAP S/4HANA Cloud: SAP Cloud Connector and SAP Process Orchestration. SAP Cloud Connector is a tool that establishes a secure connection between your on-premise system and the cloud system, allowing you to expose selected on-premise resources to the cloud. SAP Process Orchestration is a tool that enables you to design, model, implement, monitor, and optimize business processes across systems and applications. You cannot use SAP Open Connectors or SAP Cloud Integration Automation Service in a 2-tier ERP scenario. These tools are used for other integration scenarios, such as integrating third-party applications or automating integration content discovery and configuration