SAP HCI is built as Integration System-as-a-Support (PAAS) which really helps to combine multiple independent programs/apps for a company process. HCI can perform Cloud to Cloud, Cloud to On-premise, On-premise to On-premise and Hybrid product. HCI provides Adapters (Connectivity possibilities) for instance: Cleaning soap Adapter, IDoc, HTTP, Mail, SFTP,Ariba, oData. https://s4-hana-cloud-trial37137.blogdomago.com/23583207/hana-cloud-integration