title: Understanding the Concepts behind WAAD and ACS
body: <p>I understand ACS is being phased out in favor of WAAD.  As I prepare to delve into Azure for the first time I have a few questions. I already have an Azure account (linked with my MSDN account). </p>
  
  <p>Under ACS, I would create a namespace for my application, configure it with Idps and claims mapping.  I would point my application (a RESTful API via WebAPI2) to the ACS federation endpoint for my namespace.</p>
  
  <p>Under WAAD, I've seen where I can add my own application.  When I create the new application, is this creating a tenant in my directory?  I dont see where I can register my Idp's and configure the Idp's for my relying party.  In addition to authenticating via social networks (like facebook/google/etc), I'm going to want to write a custom Idp to hit against my on-premesis user store.  Is this possible in WAAD?  Finally when creating the application (tenant) in WAAD, its prompting me for a Signon URL.  Isn't WAAD supposed to manage the signon, the way it did under ACS?  when I defended a website via ACS, the user was redirected to the ACS sign in page, where they could choose from a list of Idp's for login.  Why then, under WAAD, do I, the app developer, need to code a sign on page?  I'm pretty confused about this. </p>