Subject: AI 66: SSO Profile Enhancements
My task here is to compare the "Destination-Site First" flows as found in , versus those found
In ID-FF 1.1. The latter materials may be found in Section 3.2 of  with detailed "profile" realizations in Section 3.2 of
. I conclude with some recommendations and open questions.
The ID-FF flows are pretty extensive. Here is a summary from 
Prompt the Principal for credentials if the Principal is not presently authenticated.
Prompt the Principal for credentials, even if the Principal is presently authenticated. ____
Federate the Principal's identity at the identity provider with the Principal's identity at the service provider. __ _
Issue an anonymous and temporary identifier for the Principal to the service provider. ___
Use a specific protocol profile in responding to the request. ____
Use a specific authentication context (for example, smartcard-based authentication vs. username/password- ____
based authentication). ____
Restrict or limit the identity provider's ability to proxy the authentication request to additional identity
Additionally, the service provider MAY include any desired state information in the request that the identity provider ____
should relay back to the service provider in the response. ____
In addition the <samlp:RequestAbstractType> from which <lib:AuthNRequest> is derived
always carries a unique RequestID, Version information and time instant.
I do not see any additional need for additional context information.
(a) As far as the POST profile goes,
both follow expected lines and seem quite comparable.
(b) The main differences lie in the
artifact profile. In , the artifact profile is based on a technique given in
, the mapping into a query string is carried out by "hand" and a
specific query string with certain name-value pairs described.
So the question goes to Liberty ID-FF implementers: what is your experience using URL-encoding technique in Section 3.1.2? Do you recommend we stick with it in SAML 2.0?
 sstc-bindings-extension-03 (can be found in the document repository under SAML 2.0)
Version 1.1 3