title: SAMLv2 SP initiated: One Service Provider and multiple Identity Providers
body: <p>I need to use one Service Provider with multiple identity providers(idps) each idp is connected to the sp by using a subdomain i.e. <a href="http://subdomain1.mysite.com" rel="nofollow">http://subdomain1.mysite.com</a> connects to idp1, <a href="http://subdomain2.mysite.com" rel="nofollow">http://subdomain2.mysite.com</a> connects to idp2 etc then my Assertion Consumer Service URL looks like this <a href="https://mysite.com/SAML/AssertionConsumerService.aspx" rel="nofollow">https://mysite.com/SAML/AssertionConsumerService.aspx</a>.  </p>
  
  <p>The problem is I need to know what idp the response is coming from in the AssertionConsumerService.aspx code so I can load in the right certificate. I've tried the issuer, response destination and other means with no luck.</p>
  
  <p>Does anyone know a good way to differentiate between idps from the response and/or best practices? Or is there a standard way to do this?</p>
  
  <p>I'm using <a href="http://www.componentspace.com/Products/SAMLv20.aspx" rel="nofollow">http://www.componentspace.com/Products/SAMLv20.aspx</a></p>