When configured to use authentication, you have the option to Block access on authentication failure. If you are using AD SSO and do not block access on failure, an SSO authentication failure will allow unauthenticated access without prompting the user. If you are using Browser authentication and do not block access on authentication failure, there will be an additional Guest login link on the login page to allow unauthenticated access.
When configured to use authentication, you have the option to Block access on authentication failure. If you are using AD SSO and do not block access on failure, an SSO authentication failure will allow unauthenticated access without prompting the user. If you are using Browser authentication and do not block access on authentication failure, there will be an additional Guest login link on the login page to allow unauthenticated access.