Question concerning linking of principals

["Josh Howlett" <Josh.Howlett@ja.net>]

Problem: a Relying Party wants to query some attributes for a principal
(call him principal B) that has some association with a principal (call
him principal A) that the RP already holds a Name ID for.

Would an appropriate solution be for Principal A to have some attributes
that gives Principal B's NameID and SAML attribute authority? The RP
requests these attributes, using Principal A's NameID, and then does a
second attribute request using these NameID and AA values? Are there any
other approaches to this?

Thanks for any insight... josh.

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