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<p class="MsoNormal">It is good to see Google trying new ideas with OpenID, such as their proof-of-concept for an OpenID Provider for Google hosted domains (<a href="https://sites.google.com/site/oauthgoog/fedlogininterp/openiddiscovery">https://sites.google.com/site/oauthgoog/fedlogininterp/openiddiscovery</a>).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The protocol documentation offers a Google URI for starting discovery about a hosted domain. That is, start at
<a href="https://www.google.com/accounts/o8/host-meta?hd=example.com">https://www.google.com/accounts/o8/host-meta?hd=example.com</a> to discovery the OpenID details for an example.com user (by getting a pointer to an XRDS doc that contains an OP URI to send
an auth request to).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This doesn’t scale. If Google, Yahoo, Microsoft, Xxx, Yyy… all ran OPs for hosted domains then an RP would have to try many discovery requests (and each RP would try a different subset).<o:p></o:p></p>
<p class="MsoNormal">This is probably not secure. Google could lie that is was the OP for a domain that it did not host (though I assume this is unlikely).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Perhaps Google URIs for other domains host-meta files are only a temporary hack for a demo.<o:p></o:p></p>
<p class="MsoNormal">Alternatively, there might be a significant number of groups who would like to use a hosted OP, but for whom it is still quite awkward to add even a single host-meta file to their web server.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Q. Are the Google host-meta URIs a temporary hack for a demo, or a required feature for OpenID adoption?<o:p></o:p></p>
<p class="MsoNormal">Q. Will the reported changes to JanRain’s RPX service to support the Google proof-of-concept mean that the Google URIs for host-meta are used by production RPs (such as Sears)?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">P.S. The protocol doc mentions <a href="http://example.com/.well-known/host-meta">
http://example.com/.well-known/host-meta</a> and <a href="http://example.com/host-meta">
http://example.com/host-meta</a> (for IdP and user discovery respectively. I guess one of these is a typo.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span lang="FR" style="font-size:12.0pt;font-family:"Arial","sans-serif"">James Manger</span></b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">
<br>
<a href="mailto:James.H.Manger@team.telstra.com"><span lang="FR" style="font-size:10.0pt;font-family:"Arial","sans-serif";color:blue">James.H.Manger@team.telstra.com</span></a>
<br>
</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Identity and security team</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">
</span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">—</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""> Chief Technology Office</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">
</span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">—</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif""> Telstra</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">
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