I've been reading through the various ways to configure an IdP/SP relationship and going back forth with a vendor I'm setting up our IdP to authenticate with. We've exchanged metadata and the essentials like Entity ID and login URL's, but when I go to test at the login page it fails because it can't resolve our IdP URL. As I understand it, the SP should be sending my browser a redirect to the IdP and doesn't need to access it directly.
My questions are around that understanding:
- Is it correct that as an IdP, I should be able to setup SSO as SP-Initiated, with Redirect or Post methods, without the IdP being available to the SP?
- If that's true, is there something I should be asking the vendor or SP to look at on their end in order for the redirection to take place without checking for my IdP URL?
- If it's not the case, is there another SAML method allowing for SSO to work without exposing the IdP to the internet?