Creating SAP Transaction IView - System Comes From??

I am attempting to create a new SAP Transaction IView...where does the system property pull the drop-down list of systems from. I thought I had a connection to our R/3 system created, but it does not show. We are just starting to play with EP6, but I'm stuck on this one. Where is this system created so that it appears as a selection for the creation of the IView.

Thanks in advance....