SAP HCI is built as Integration System-as-a-Company (PAAS) which helps to combine many unbiased devices/apps for a company course of action. HCI can perform Cloud to Cloud, Cloud to On-premise, On-premise to On-premise and Hybrid design. HCI gives Adapters (Connectivity possibilities) for example: SOAP Adapter, IDoc, HTTP, Mail, SFTP,Ariba, oData. https://s4hanacloudportal25691.onesmablog.com/hana-cloud-integration-68611455