Online tracking system

Hi Experts ,

I have a scenario in which I have a webportal on one side and SCEM(supply chain event management ) on the other side and integration is through XI.

Now my question is on my webportal a user logs on and give his details e.g. an invoice no. for tracking his material.now that detail i.e invoice no. flows to my SCEM through XI and i get the current status of material e.g in case of shipments it shows the current location of where material has reached .

Now i want to flow back this information back to the user on the web portal through XI.

How can we do this .?

Does anyone give any architectural overview of integration XI and SCEM?

Regards

Saras Jain