@Sumeetha Mogasati Thank you for your query!!!
You can refer to below for the details around MCAS. It has all details and is our official documentation in one place:
Below documentation might help you understand the architecture side of it:
Following article provides best practices for protecting your organization by using Microsoft Cloud App Security:
Below doc will help you understand MCAS in depth:
I would recommend you to go through the above documentation they have lot of information and hence time taking but will surely help you out in understanding MCAS Design and functioning better.
Hope it helps!!!
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