Use SAP ADSO Writer Connector to connect to the SAP BW/4HANA on-premise application.
You can use SAP ADSO Writer Connector to create an application server connection or a load balancing connection to connect using the SAP user name and password. You can also use create a Secured Network Application (SNC) application server connection or a load balancing connection to connect to SAP BW/4HANA using the SNC parameters.
You must create a connection to SAP BW/4 HANA on-premise systems before designing the mapping or mapping task.