This page is now only of historical interest.
This is now 6.2.10, because of changes made in response to other change proposals.
I have left this in. I agree that it does not belong in the spec in the long term. But, until we have the Overview and Implementer's Guide, it is important to mention this. We don't want readers to be mystified, wondering what this is all about. It is, after all, in the first instance, about discovering authentication services.