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</o:shapelayout></xml><![endif]--></head><body lang=EL link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>In siop v2 (<a href="https://openid.net/specs/openid-connect-self-issued-v2-1_0.html#name-self-issued-id-token">https://openid.net/specs/openid-connect-self-issued-v2-1_0.html#name-self-issued-id-token</a>) when it comes to the “self-issued ID Token” section 12 says:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>“sub[…]When Subject Syntax Type is JWK Thumbprint, the value is the base64url encoded representation of the thumbprint of the key in the sub_jwk Claim”<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Then, a example follows where the “sub” claim is indeed a base64url encoded representation of key thumbprint. However, in section 12.1 the text says:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>“The RP MUST identify which Subject Syntax Type is used based on the URI of the sub Claim. Valid values defined in this specification are urn:ietf:params:oauth:jwk-thumbprint for JWK Thumbprint Subject Syntax Type and did: for Decentralized Identifier Subject Syntax Type”<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>This confuses me. Which of the following is the correct syntax for the sub claim when Subject Syntax Type is JWK Thumbprint: <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>"sub": "NzbLsXh8uDCcd-6MNwXF4W_7noWXFZAfHkxZsRGC9Xs",<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Or<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>"sub": "urn:ietf:params:oauth:jwk-thumbprint:NzbLsXh8uDCcd-6MNwXF4W_7noWXFZAfHkxZsRGC9Xs",<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Best,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Nikos<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>--------<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Nikos Fotiou - </span><a href="https://www.fotiou.gr"><span lang=EN-US style='color:#0563C1'>https://www.fotiou.gr</span></a><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Researcher - Mobile Multimedia Laboratory<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Athens University of Economics and Business<o:p></o:p></span></p><p class=MsoNormal><a href="https://mm.aueb.gr/"><span style='color:#0563C1'>https://mm.aueb.gr</span></a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>