Answer :
- By default, NTLM is used for authentication
Explanation :
Tableau Server does not perform this authentication. By default, NTLM is used for authentication, but you can enable Kerberos or SAML for single sign-on functionality. However, in all these cases, authentication is left to Active Directory. However, the Tableau user names stored in the identity store are associated with rights and permissions for Tableau Server. Therefore, after authentication is verified, Tableau Server manages user access (authorization) for Tableau resources.