title: REST web service Basic authentication + Client Facebook app authentication = double authentication?
body: <ol>
  <li><p>I have built a web service based on a REST design. Of course some of the operations available on resources require authentication (delete a user for example). I use Basic authentication and so far everything is fine.</p></li>
  <li><p>I have built a client to consume the web service : a set of Ajax function. Again, everything is fine (also for the Basic authentication).</p></li>
  <li><p>I want now to create a whole web app that will use the set of Ajax function above to interact with the web service. But, to enhance the user experience, some of the web app functions will require Facebook authentication.</p></li>
  </ol>
  
  <p>So here is my problem. The web app will require username and password to call the web service via the Basic authentication. But it will also require Facebook credentials to use Facebook API and the user will have to log in twice. Moreover, every time I will have to check if the Facebook user (currently logged in Facebook) corresponds to the user of the web service and it is quite troublesome.</p>
  
  <p>Does anyone have an idea to simplify the process ?</p>
  
  <p>It's a bit related to that post <a href="https://stackoverflow.com/questions/6462863/authentication-scheme-for-multi-tiered-web-application-utilizing-rest-api/6463357#6463357">authentication-scheme-for-multi-tiered-web-application-utilizing-rest-api</a> but I did not find any answer I could understand.</p>