The threat of brute force attacks especially through the RDP (Remote Desktop Protocol) protocol and ransomware threats are the main focus of this Duo Security feature.
The Duo Security feature is there to protect critical services such as the RDP protocol on Windows Server.
Basically, this Duo Security feature is a 2-step secure login validation to anticipate third parties who can log into your server without your knowledge. Duo Security functions to validate with 2 steps to ensure that those who can log in and the session that logs into the server are real users and truly authenticated users.
Allow / Reject User
By using Duo Security, you can find out exactly who is trying to log in and immediately appear notification notifications on your cellphone. Make sure you install the Duo Mobile app on your phone first.