Security Architecture and Design - Business Analytics Logical Data Flow

How can the analysis system gather data from all these sources, that presumably, are protected themselves? 

Please look at the image attached for the diagram of the data flow octopus. 

Criteria: 

Read Chapter 8 in the attached textbook thoroughly

400 words minimum

APA citation - intext and end of the paper bibliography

Minimum of 2 references (including the textbook)