Could you explain in details what method is this comparing to integrating with AD?
If you look at the document linked, you'll see that you can setup SAML using a couple different identity providers. Including AD Federated Services and Azure AD. You can also do a bit of basic digging on SAML, since it's a standard SSO method.
Yea, heard about Duo. But my customer would like to just integrate with their existing AD for the authentication access to Dashboard. The only concern of the customer is if one of the current administrator resign from the company, the admin doesn't need to remove the resigned staff from the Dashboard if it is integrated with AD. Does the SAML SSO able to implement to serve this purpose?