When suspicious network activity is detected, a Security notification is generated:
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Drilling down on the critical security status leads to a more detailed description of the notification, showing that port scanning has been detected:
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The host 172.16.144.52 has been observed connecting to 372 hosts using port TCP:445 and 247 hosts using port TCP:139
Clicking on the link for 172.16.144.52 provides additional information about the host.