Windows Azure Active Directory (Windows Azure AD) is an identity service that can be accessed through RESTful services. This means that there can be one identity service for Windows Azure, Windows Intune, Dynamics CRM Online, Microsoft Office 365, third party cloud services and on on-premises AD.
This is a bit mind-blowing. Windows Azure AD makes it possible to extend an existing AD implementations into the Cloud. This also means that a single sign-on for Cloud based applications would be possible.
As part of learning more about Identity in Windows Azure, I came across the Windows Azure Authentication Library (AAL). From what I have been able to learn. It appears that AAL is a wrapper around Windows Azure AD.
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