Active Directory Federation Services (ADFS) was introduced in Windows Server 2003 for organizations that need to participate in standards-based identity federation. With ADFS, you can more easily validate identity data from other organizations, leading to greater interoperability with your partners.
In the December issue of MSDN Magazine, Jack Couch takes you on a guided tour of ADFS in action, demonstrating how one online service provider could use ADFS to interact with a second online service provider and a shared customer. By using Active Directory Application Mode (ADAM) in conjunction with ADFS, you can enable single sign-on (SSO) so that customers don't have to remember a multitude of passwords.
For more on networking and Active Directory development, see our MSDN Magazine archives.