1. Go to transaction SALE define logical systems .
2. Assign client to the logical system using transaction SALE.
3. Goto SM59 and Create RFC destination .
4. Goto WE21 and define port by which data is transferred.
5. Goto WE20 and specify the the name of the partner which is allowed to send idocs.
6. Goto BD61 Check the box so that change pointers get activated and keep track the changes to trigger ALE process.
7. Go to BD50 Activate change pointers for required message type .
8. Goto BD64 and setup a Distribution model .Apply the filter on the fields to restrict the idoc generation.
9. Use RBDMIDOC program to generate IDOC .