Duo Admin
In this document you are going to set up IDmelon as an external IdP to the Duo Admin.
Login to Duo Admin administration panel
To enable administrator SSO:
Role required : Owner
Log in to the Duo Admin Panel.
Click Administrators in the left sidebar, and then click Admin Login Settings.

Add Identity Provider
Then Scroll to the Single Sign-On with SAML Configuration section of the "Administrator Login Settings" page.
Enable SSO by changing the "Authentication with SAML" setting. The options for this setting are:
Disabled
Optional
Required

Selecting the Optional or Required SAML authentication option exposes the rest of the SSO configuration form. You’ll need to enter below information about IDmelon identity provider in the SAML Identity Provider Settings section:
Identity provider: Custom Identity Provider
Configuration method: Manual entry
Configure SAML 2.0 IdP
Get all values for {..} from your IDmelon panel.
If you are currently login here, you will see the replaced values instead.
Entity ID or issuer ID: idp_issuer_uri
Assertion consumer service URL or single sign-on URL: idp_single_sign_on_url
Single logout URL: idp_single_sign_on_url
Certificate: idp_certificate_download_url
Encrypt assertions: Require unencrypted assertions
Request signing: sign messages from Duo

SHA-1 signatures: Uncheck
Signed elements: Everything must be signed
Click Save

IDmelon SAML configuration
You should Download metadata file(XML file) and copy values of below fields from this Duo panel to IDmelon Panel.

Copy Entity ID or Issuer ID
Copy Assertion consumer service or single sign-on URL
You should copy values of below fields from this Duo panel to IDmelon Panel.