Overcast typically communicates with SAP ERP directly via SAP standard Business APIs (BAPIs & RFCs) – the same way SAP applications interact with each other. That is extremely performant and there is no overhead. The BAPIs apply business logic and do authorization checks.
However, when desired, the Overcast App and the Overcast Components can also optionally integrate with SAP through SAP PI, SAP PO or SAP CPI (“SAP PI”) and leverage existing integrations that you may have already built.
Overcast can call SAP PI web services with ease and also receive change triggers from SAP PI, in order to “push” data from SAP to Salesforce.
For the pre-built, pre-integrated Overcast Components to work via SAP PI, the required SAP BAPIs need to be exposed via SAP PI upon specifications provided.