WebServerAuth
WebServerAuth allows Plone to delegate authentication concerns to a web server like Apache or IIS. Using WebServerAuth, Plone can be configured so any user known to your LDAP, Kerberos, Shibboleth, or Pubcookie system—or any other system for which your web server has an authentication module—can transparently log in using enterprise-wide credentials. WebServerAuth obsoletes and improves upon apachepas and AutoMemberMakerPasPlugin, which come significantly and entirely, respectively, from the same author.
The link address is: http://plone.org/products/webserverauth
