The other point that was made at the meeting is that we do not want to duplicate the subject attributes in the confirmationMethod as is potentially being done in the example below. Also we need to state quite clearly what is the semantic difference between a subject attribute (such as a portrait) and the identical confirmation method attribute (such as a portrait). This requires the following questions (at least) to be answered

Can the former not be used for confirmation by the verifier or can it be used?

Does the former need to be duplicated in confirmationMethod before it can be used for confirmation?

What are the reasons (if any) that any subject attribute cannot be used for confirmation by a verifier regardless of whether a confirmationMethod for it exists or not.

Kind regards

David

On 21/02/2023 02:30, Oliver Terbu wrote:

Example (not normative):

...

"confirmationMethods": [ {

    //refers to credentialSubject.id and can be defined //as verify the VP and that the VP is signed with linked DID

    "type": [ "SubjectDidAuthenticationConfirmation2023" ]

}, {

    "type": [ "PassportConfirmation2023" ] ,

    "nationality": "NL",

    "passportNumber": 012345678,

    "contentHash": "3338be69 ... 2398f392"

}, {

    "type": [ "BiometricTemplateConfirmation2023" ] ,

    "portrait": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAA8sAAAJl..."

}, {

    "type": [ "BiometricTemplateConfirmation2023" ] ,

    "linkedPortrait": "credentialSubject.userPicture" //refers to existing claim

}]

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