I am trying to gather as much information as possible to make a recommendation of using XI for transporting multiple (large) files into SAP SRM mainly. There is also the possibility of getting back some data from SRM.
We are looking for the best solution that would help us achieve this - probably make RFC calls and get back Idocs (using JCo if you have to) or using SOAP to access the information/data from SAP MDM / SRM
I would recommend that where possible try to use ABAP Proxies rather than IDOCs or RFCs.
SAP has provided a lot of standard content for connecting to SRM using XI. You should explore that to see if any of it suits your requirements... it will reduce your effort and time for implementation.
If you are using SAP systems (R/3 or SRM or any other SAP system), my first choice would be to see if I implement a PROXY. As this is possible only for WAS 6.40 or above, if your system is not there yet, then my second choice would be to see if I can use a IDOC Adapter. And then finally the RFC Adapter.
However, for files we do NOT have choice and have to go with file adapter. (Your design will change depending on whether its a flat file or XML file etc etc). Coming to MDM, right now MDM can interact only with files. So, even if you are sending IDOC's, they will have to be written into files and MDM can read the same.
Take a look at this blog.
Let me know if you have more questions.
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