Thanks,
Greg
I found more info from SDK documentaion. Hope it helps everyone.
IDSSDataSourceEnumerator interface returns a collection of DSSDataSource handles upon request from DSS applications such as the MicroStrategy Desktop.
DSSDataSource interface is used to support the client to connect to a server or to create a session to connect to a project DSSDataSource object is created for the client by the DSSSourceEnumerator object.
IDSSSession interface provides a context that the client can get the required components and use the components.
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