This Recommendation enables discovery:
o for relevant information about identifiers, including those utilizing e-mail address syntax and those that are URLs as well as persistent identifiers;
o of attributes about identity providers and relying parties, including, but not limited to visual logos and human-readable site names;
o supporting a spectrum of clients, ranging from passive clients to active clients with bootstrapping functionality;
o of authenticable attributes and add-on functionality of non-browser applications;
o of trust frameworks, policies and references.