title: Azure AD B2C and on-premise Active Directory
body: <p>We have the following scenario:</p>
  
  <ul>
  <li>an Angular app accessing a Web Api backend</li>
  <li>our own user database</li>
  </ul>
  
  <p>We are planning to use a third-party identity solution such as <strong>Azure AD B2C</strong>, <strong>AWS IAM</strong> or <strong>Auth0</strong>.  To my surprise, I found that Auth0 has an integration with on-premise Active Directory, but Azure AD B2C seems not to support this (at least not that I could find out)  </p>
  
  <p>We want to get to the following scenario:</p>
  
  <ul>
  <li>an Angular app accessing a Web Api backend</li>
  <li>third-party identity solution that manages the users of the angular app (preferably Azure AD B2C)</li>
  <li>users need to authenticate via the identity solution (e.g. using a social account)</li>
  <li>some users are in an existing on-premise AD and also need to be able to access the angular app</li>
  </ul>
  
  <p><strong>So my problem basically is</strong> : if we would use Azure AD B2C, how can we let users that are defined in an on-premise AD, authenticate in our Angular app? Or with other words: can an on-premise AD be an identity provider for Azure B2C?</p>