Merge pull request #257 from w3c/iana-considerations

Add IANA Considerations

spec.bs

@@ -69,6 +69,7 @@ spec: web-authn; urlPrefix: https://w3c.github.io/webauthn/
         text: client extension; url: client-extension
         text: registration extension; url: registration-extension
         text: authentication extension; url: authentication-extension
+        text: extension identifier; url: extension-identifier
 
 spec: webdriver; urlPrefix: https://w3c.github.io/webdriver/
     type: dfn
@@ -93,6 +94,11 @@ spec:url; type:dfn; text:valid domain;
     "webauthn-conditional-ui": {
         "title": "WebAuthn Conditional UI Proposal",
         "href": "https://github.com/w3c/webauthn/issues/1545"
+    },
+
+    "IANA-WebAuthn-Registries": {
+        "title": "Registries for Web Authentication (WebAuthn)",
+        "href": "https://www.rfc-editor.org/rfc/rfc8809.html"
     }
 }
 </pre>
@@ -1636,3 +1642,14 @@ should apply [=bidi isolation=] around displayable string values
 when inserting them into the user interface. They should set the
 direction when it is known, or default to first-strong ("auto")
 when it is not.
+
+# IANA Considerations # {#sctn-iana-considerations}
+
+This section adds the below-listed [=extension identifier=] to the IANA "WebAuthn Extension Identifiers" registry [[!IANA-WebAuthn-Registries]] established by [[!RFC8809]].
+
+- WebAuthn Extension Identifier: payment
+- Description:  This extension supports the following functionality defined by the Secure Payment Confirmation API: (1) it allows credential creation in a cross-origin iframe (2) it allows a party other than the Relying Party to use the credential to perform an authentication ceremony on behalf of the Relying Party, and (3) it allows the browser to identify and cache Secure Payment Confirmation credentials. For discussion of important ways in which SPC differs from Web Authentication, see in particular [[#sctn-security-considerations]] and [[#sctn-privacy-considerations]]
+- Specification Document: Section [[#sctn-payment-extension-registration]] of this specification
+- Change Controller: [W3C Web Payments Working Group](https://www.w3.org/groups/wg/payments)
+- Notes: Registration follows [3 May 2023 discussion](https://www.w3.org/2023/05/03-webauthn-minutes#t01) with the Web Authentication Working Group.
+