ActiveDirectory is a core Microsoft Server product, and ActiveDirectoryFederationServices (code name TrustBridge) is an IdentityManagement scheme for related servers that will be made available in WindowsServerTwoThousandThree R2 upgrade.
See a 20 page overview document at http://download.microsoft.com/download/d/8/2/d827e89e-760a-40e5-a69a-4e75723998c5/ADFS_Overview.doc
A key advantage of this InformationSecurity related offering is to protect intranets that need to be linked up to less than trustworthy WirelessDevices. Thus a single external firewall will no longer be adequate to protect corporate networks.
Aha, another WS-ReinventTheWheel. Can anyone tell us why we should take this seriously, complete with new language etc? Check out SAML2.0/Liberty etc.
Response to RichardHenderson query
You may be interested in May05 article "Microsoft's Vision for an Identity Metasystem" where relationship between the OasisOrganization SecurityAssertionMarkupLanguage specs and implementation is discussed. See http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnwebsrv/html/identitymetasystem.asp
After you are through, pls move the above link to Resources section in WebServicesInteroperabilityConcerns. You may wish to add your views to that page instead. DeleteWhenCooked
See also WebServicesInteroperabilityConcerns