FBA pointing to Active Directory

SharePoint and ExCM can use any Membership provider for operations like authentication, add users, reset passwords. The .NET framework provides two membership providers out-of-the-box (ActiveDirectoryMembershipProvider, SQLMembershipProvider). You can use the ActiveDirectoryMembership provider to connect to AD or AD LDS (ADAM). MOSS 2007 comes with an an additional provider named LdapMembershipProvider which can be used to connect to AD via LDAP or other LDAP sources. However, not every provider supports the same operations and the AD/LDAP providers can be more difficult to implement.

When selecting a provider you also have to think about Role and Profile providers. SQL supports all three provider types. AD supports only membership and the LDAP provider supports membership and roles. This is the reason why most customer choose to implement SQL membership, because it is fully functional and scales well. Please take a look at some of the links below for more information...

General

(Authentication Samples)
http://technet2.microsoft.com/windowsserver/WSS/en/library/91035419-980e-4230-b3ae-67253b94af4a1033.mspx?mfr=true

(Plan authentication settings)
http://technet.microsoft.com/en-us/library/cc288081.aspx

(Forms based authentication in MOSS)
http://blogs.msdn.com/harsh/rss_tag_FBA.xml

(How to use Membership in ASP.NET 2.0)
http://msdn2.microsoft.com/en-us/library/ms998347.aspx

LdapMembershipProvider

(LDAP Membership Provider Class)
http://msdn2.microsoft.com/en-us/library/microsoft.office.server.security.ldapmembershipprovider.aspx

(Configure forms-based authentication against an LDAP data store in Office Project Server 2007)
http://technet.microsoft.com/en-us/library/cc197721.aspx

(Moss LDAP Membership Provider)
http://blog.hametbenoit.info/Lists/Categories/Category.aspx?Name=Security

(Using LdapMembershipProvider in SharePoint, and get it to work!)
http://www.sharepointblogs.com/rhulsman/archive/2006/12/12/using-ldapmembershipprovider-in-sharepoint-and-get-it-to-work.aspx

ActiveDirectoryMembershipProvider

(Active Directory Membership Provider Class)
http://msdn2.microsoft.com/en-us/library/system.web.security.activedirectorymembershipprovider.aspx

Alternate Access Mappings

(Plan alternate access mappings)
http://technet2.microsoft.com/windowsserver/WSS/en/library/c8ccffce-5162-46af-a3ef-1d7914e8efee1033.mspx?mfr=true

(Configure alternate access mapping)
http://technet2.microsoft.com/windowsserver/WSS/en/library/8642f748-f169-4799-8fe9-8140fbb23fbf1033.mspx?mfr=true