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Having a clear set of requirements is one important prerequisite to creating a level playing field on which multiple IdPoLRs can play. Another is some form of tagging of IdPoLR services. One of the ways to meet both of these prerequisites would be by leveraging emerging practices in the entity category space. The REFEDS Research and Scholarship Entity Category specification (httpshttp://refeds.org/category/research-and-scholarship/) provides a concrete example of this approach in action. The requirements and conditions on qualifying services would be spelled out in the document formally defining the category. It would likely have to be managed as a self-asserted tag by IdPs who would commit themselves to meeting all the requirements. An alternative would be to have a federation register and vet candidate IdPs. However, that would place an onerous burden on the federation which would have to define a set of processes and devote staff time to the registration, vetting and marking of IdPoLRs. Another alternative would be for some organization representing R&S service providers to maintain a list of qualifying IdPoLR services. Regardless of this, nothing would prevent an individual R&S SP from making it's own determination of which, if any, IdPoLRs it would accept.
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