[KI-LC] Call for Votes: Concordia DG Interim Report - Deployment Guide for Proxying Assurance between OpenID and SAML

Bob Pinheiro kantara at bobpinheiro.com
Thu Jun 3 11:02:01 EDT 2010

Even though I already voted in support of acceptance, one thought does 
occur to me which maybe (or maybe not) would be useful to address in the 
Motivation section of the report.  The point is made that a SAML RP 
might request an assertion from a SAML IdP at a lower LOA than supported 
by the IdP; therefore the IdP may want to proxy to an OpenID OP that can 
provide the lower level assertion.  Although this document isn't meant 
to address business issues, I wonder why the SAML IdP wouldn't just 
provide the lower level assertion or claim itself.  There are two issues 
I can think of that would come into play.  One is that the higher level 
assertion or claim would be more robust or contain more information than 
would be required for a lower level claim/assertion.  But why couldn't 
the SAML IdP just provide a watered-down claim/assertion to satisfy the 
lower assurance request?  And since the subject already has higher 
assurance credentials issued by the SAML IdP, those same credentials 
would still be good for the lower assurance authentication.

The second issue is that presumably the higher level claim/assertion is 
more "expensive" for the IdP to provide.  Depending on the business 
model in play to compensate the IdP for its trouble, the SAML IdP could 
just "charge" the RP a lower price for the lower level claim/assertion 
(if that is the business model in use), or could provide it for free, 
since OpenID providers don't charge anybody for their low assurance 
assertions anyway.

I think there's an underlying assumption that people may use SAML IdPs 
for their high assurance identity needs, and OpenIDs for their low 
assurance needs.  It may more likely be the case that the need for 
multiple IdPs revolves around the kinds of SPs/RPs that people will 
interact with.....so financial SPs/RPs may trust certain IdPs, 
healthcare SPs/RPs may trust different IdPs, etc.  depending on which 
IdPs/OPs are conformant to different trust frameworks that may emerge 
for these different communities.  Or maybe not.  Anyway, these kinds of 
issues are probably better addressed elsewhere.....maybe in the Consumer 
Identity WG.


Bob Pinheiro
Chair, Consumer Identity WG
kantara at bobpinheiro.com

On 6/1/2010 3:11 PM, J. Trent Adams wrote:
> All -
> This is a call for you to vote on the following motion regarding the
> acceptance of an Interim Report from the Concordia Discussion Group.
> Please reply according to the options listed below.
> -----
> MOTION: To accept the Concordia Discussion Group Interim Report titled
> "Deployment Guide for Proxying Assurance between OpenID and SAML" as
> submitted to the Leadership Council Secretary on June 1st, 2010. [1]
> -----
> Your options:
>   A. Reply with any discussion on this motion prior to voting.
>   B. Reply to this message with a "YES" if you support the
>        acceptance of the interim report.
>   C. Reply to this message with a "NO" if you do not support
>        accepting the interim report.  Also, please include your
>        rationale for a "NO" vote.
>   D. Reply to this message with an "ABSTAIN" if you abstain.
> The deadline for voting is Tuesday, June 8th at 23:59 UTC.
> This vote requires a Simple Majority to pass (i.e. more than 50% of
> votes received - excluding abstentions).
> Thanks in advance,
> Trent
> [1]
> http://kantarainitiative.org/confluence/download/attachments/41650124/Kantara-concordiadg-proxyingassurance-report-08.pdf?version=2&modificationDate=1274824442000

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