Hi @Vinod Survase ,
To address your first question, Microsoft Defender for Cloud Apps (previously known as Microsoft Cloud App Security) can monitor user activity across Exchange Online, SharePoint Online, OneDrive for Business, Teams, and more. For a full list of Office 365 activities monitored by Defender for Cloud Apps, see Search the audit log in the compliance center and Activity Filters. It can also detect and alert on suspicious behavior, such as data exfiltration, malware, and phishing attempts. Additionally, it provides advanced analytics and reporting capabilities to help you gain insights into your organization's security posture and identify areas for improvement. See Microsoft Defender for Cloud Apps - Overview
As for your second question, if you don't want to notify users that they're being monitored, you can disable the notification message. To do this, follow these steps:
- Select the Settings icon (cog), and then select General settings.
- Under Conditional Access App Control, select User monitoring, and then clear the Notify users check box.
The sessions will still be monitored by Microsoft Defender for Cloud Apps but the notification will go away. See: Troubleshoot - Access is monitored
Other references:
How to investigate anomaly detection alerts
Connect Office 365 to Microsoft Defender for Cloud Apps
Let me know if this helps and if you have further questions.
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