In this post, Premier Dev Consultant Marius Rochon considers scenarios where an application needs to be accessed by users from many sources of authentication (Office 365, owned and operated by Microsoft but whose use is managed separately by many independent organizations is an example of such a resource). It proposes a framework for determining an optimal solution for the application using Azure AD.
The optimal identity infrastructure architecture to minimizes security risks, maximizes utility of authentication while minimizing its cost. In particular, providing single sign-on reduces the risk of user compromising their credentials (because they have to remember several). Also, having the credential managed outside of the application removes from it the cost of its management (storage, associated call center services, etc.).
However, providing SSO to users from many identity directories involves solving at least two technical problems. These are described in more detail below as Issues. The Discovery section describes a taxonomy that seems useful in understanding authentication requirements. These requirements are then used to identify distinct identity directory architectures addressing the cost/benefit objectives described above.