Use Case 2: Manage Amazon EC2 instances
Using familiar Active Directory administration tools, you can apply Active Directory group policy objects (GPOs) to centrally manage your Amazon EC2 for Windows or Linux instances by joining your instances to your AWS Managed Microsoft AD domain.
In addition, your users can sign in to your instances with their Active Directory credentials. This eliminates the need to use individual instance credentials or distribute private key (PEM) files. This makes it easier for you to instantly grant or revoke access to users by using Active Directory user administration tools you already use.