The external service wizard is a tool you use to create services. The external service wizard establishes a connection to the SAP server, discovers services (based on search criteria you provide), and generates business objects, interfaces, and import or export files, based on the services discovered.
Using IBM® Integration Designer, you establish a connection to the SAP server to browse the metadata repository on the SAP server. The SAP metadata repository, which is a database of the SAP data, provides a consistent and reliable means of access to that data.
The result of running the external service wizard is a module that contains the interfaces and business objects along with the adapter. You can deploy this module on IBM Business Process Manager or WebSphere® Enterprise Service Bus.