this scenario you are developing ASP.NET MVC web application and you need to implement authentication using either Internet identities such as Live ID, Google, Facebook, Yahoo!, or OpenID 2.0 or enterprise identities managed by corporate Active Directory.
Windows Azure AppFabrice Access Control Service (ACS) is used to solve this scenario.
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Richard Mueller edited Revision 12. Comment: Fixed duplicate <a name> tags in headings in HTML so TOC works, removed (en-US) from title, added tags
Excellent !!! Diagram helps to know the concept.
Carsten Siemens edited Revision 15. Comment: Fixed typos