Hello there Víctor!
Your assumption is correct. The iViews reference a System Alias, and the System Alias belongs to a System Object.
The System Object is a portal representation of the actual system to which the portal connects to retrieve the expected application. Following you can find a good explanation:
How to Create System Object in the Portal for Connecting to SAP backend System - Portal - SCN Wiki
Hope to have clarified your question!
Cheers,
Armando
