title: SP2010 mixed authentication, windows and forms, both against AD
body: <p>I want to have a mixed mode SharePoint 2010 install where intranet users are authenticated via Windows Authentication, and extranet users are authenticated via forms authentication.</p>
  
  <p>There is an existing solution here, <a href="http://www.orbitone.com/en/blog/archive/2010/06/23/sharepoint-2010-mixed-authentication-automatic-login.aspx" rel="nofollow">http://www.orbitone.com/en/blog/archive/2010/06/23/sharepoint-2010-mixed-authentication-automatic-login.aspx</a>, but I have one unusual difference. In most cases, the Windows authentication goes against an AD server and the forms authentication goes against an ASP.Net membership database. In my case, they're both going against AD servers. The users who use forms authentication are stored on an extranet AD server, and the users who use Windows authentication are stored on an intranet AD server. The extranet AD server has pass through authenciation set up with the intranet AD server, so SharePoint is always directly connected to the extranet AD server.</p>
  
  <p>Is there a better approach to automatic mixed mode authentication in this case?</p>