Retrieving VCT metadata

[samuelmr]

SD-JWT VC 6.3. Retrieving Type Metadata defines many ways to retrieve Type Metadata:

• From a URL in the vct Claim
• From a Registry
• Using a Defined Retrieval Method
• From a Local Cache

Should we limit the list of requirements for DIIP? Perhaps by stating that only the first option (From a URL in the vct Claim) must be supported?

[samuelmr]

Do we want to say anything about Document Integrity?

[muisit]

It would be good for completion sake to state that the first option MUST be supported.
I assume document integrity is not difficult to implement on either side, so I'd suggest to make that a MUST as well.