Am I right, that LdapAuthentication.php at present
does not
offer a single_sign-on access but "only" the security of
authentication, so that only authorized people have access to
the company's wiki?
Well, it depends on what you mean. Single sign on is kind of a generic
term.
The LDAP Authentication plugin does support CAC/Smartcard
authentication, and most auto-auth plugins can be (slightly) modified to
work with the LDAP plugin.
If you mean kerberos or ntlm, neither one currently work with the
plugin.