Looks like you are confused. Routing rules are required only to route the IDOCs to the SAP R3 based on the Sender, Receiver and Message Type combinations. Generally, it is not required when you do a OutboundProcess directly in your SAP BC Service.
Regarding the data transfer, please follow the following steps.
Create a new PORT in the SAP BC as “webMethods/FTP Port”.
Give any number, mention the package name and save. Also change the Access mode to “Allow by default” or specify the Legacy systems IP address only.
By this you have created a FTP Port on your SAP BC.
Further to this, your Legacy system can use “ftp-put” to send data to the IS.
Here, the ftp directory path must be like, for example (/ns/FTPDemo/get) if the servicenamespace is FTPDemo:get
The BC service will have a contentStream object as the input and the first step is to use the “streamToString” service which converts the stream into a string.
This can be further converted to a IDOC using xmltodocument and transformhierarchytoflat.
HTH and have fun.
Bhavani Shankar
Note :
Please refer SAPBCAdministrationGuide.pdf. This will give more details on how to configure ports and allow access. (Note, the PDF file name could be different, but it is surely Adminstration.pdf and available in the docs folder of your SAP BC Server setup.)
#Adapters-and-E-Standards#Integration-Server-and-ESB#webMethods