When implementing MDM, do we also need XI for the interfaces with external systems ? (I want to use MDM as a repository for materials and customers, and distribute them to SAP as well as non SAP systems).
If not, what is the technical infrastructure required ?
while implementing MDM for master data you definitely need XI for data exchange.As per your requirement after creating a logical system(which may be identified by BASIS or XI team) you map it in we* trans codes for IDOCs or you may even use RFCs. What you do is you pass this idoc or RFC number to concerned XI team which is then responsible to convert this IDOC to xml.You can then send XMls to your SAP as well as legacy systems.However in Real Scenarios we generally have a separate XI team which coordinates with MDM team for data transfer.
Please ark helpful answers
you don't necessarily need XI, but the more systems you want to integrate, the more useful XI gets because of its format converting functions.
Yet, if you don't want to use it, you can use the port concept or flatfiles for communication with other systems.
With the port concept you can somewhat automise the process.
Hope this helps,