System Connections
The system connections are the links and connections that move data from a data source to a data destination. System connections are available in the All Connections folder of the Data Sources tree view tab.
Each system type has at least one system connection which you can manage through the system properties window. Working with System Properties
Staging systems have two connections; one from the data source, the other to a staging database. A linked source also has two connections; from a linked data source, to a temporary database. All other system types have only one connection.