Zuar Portals can be configured to use Tableau Server/Online for authentication.
The configuration includes a Tableau Server/Online URL and Site.
Users who authenticate to Tableau Server/Online with basic authentication (local, Active Directory, or LDAP identity stores) can log into a Zuar Portal with the same credentials (username and password). Read more about Tableau authentication.
Zuar Portals can also leverage Tableau Server's Trusted Authentication.