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Hello FastFed WG,
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<div class="">The current draft spec defines an extension to Webfinger using subdomains</div>
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<div class="">The subdomain location is determined by prefixing the email domain</div>
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<div class=""> with ""webfinger._well_known"". For example, if the user email is</div>
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<div class=""> ""<a href="mailto:babs@example.com" class="">babs@example.com</a>"", the resulting Webfinger endpoint is</div>
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<div class=""> ""<a href="https://webfinger._well_known.example.com" class="">https://webfinger._well_known.example.com</a>"".</div>
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<div class=""> Application Providers performing WebFinger discovery MUST first</div>
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<div class=""> attempt to read from the subdomain endpoint. If the response is not</div>
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<div class=""> an HTTP 200, the Application Provider MUST subsequently attempt</div>
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<div class=""> reading from the traditional WebFinger path at the root domain. A</div>
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<div class=""> non-normative example is illustrated in Section 4.1.2.1.2.</div>
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<div class="">I remember discussing this at IIW last year and wasn’t sure if we settled on this approach. I remember some folks saying that this approach wouldn't fly in IETF land. Alternative approaches such as DNS SRV or TXT records were also discussed.
Folks liked the simplicity of using DNS host records so that devs could just plop it into a connection string and the magic of the URL would do its thing.</div>
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<div class="">We have an internal use case for discovery of an openid issuer based on email suffix where customers don’t want to host a webfinger endpoint. Customers *might* be able to delegate the entire webfinger endpoint to our SaaS using a subdomain but
it might not be something we are authoritative for for all webfinger queries.</div>
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<div class="">We were looking at <a href="https://tools.ietf.org/html/draft-sanz-openid-dns-discovery-01" class="">https://tools.ietf.org/html/draft-sanz-openid-dns-discovery-01</a> as a possible solution to serialize webfinger results in a TXT record. This
removes the need for administrators to maintain (scale, availability, etc) an endpoint for webfinger for relatively static results such as issuer which can be cached. I could see us extending this to support a fedfed tag as well. The dev friction of using
TXT records is slowly being ameliorated as DNS over HTTP becomes mainstream (see <a href="https://developers.google.com/speed/public-dns/docs/doh/json" class="">https://developers.google.com/speed/public-dns/docs/doh/json</a>). I’m making assumption that
the admin friction of creating TXT records is similar to host/subdomain records which may not be true for all enterprises.</div>
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<div class="">Is it worth rehashing this topic or has it already reached consensus in the WG? </div>
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<div class="">-Karl</div>
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