Introduction
VCDM 2.0 introduces processing clarifications, transitions into an actual data model, media types, data model simplifications while still having the VCDM 1.1 baseline, and much more. EBSI will promote the 2.0 by using it in the Conformance Test v4, in EBSI-specific Verifiable Authorisations, and in the Trust Model.
The 2.0 data model is still in draft, but it is not expected to have major breaking changes. The clarified separation of the data model from the securing mechanism is a significant feature that allows a richer ecosystem to exist. EBSI will keep all important intermediate schema versions, which are implemented in Verifiable Attestation and uploaded into Trusted Schema Registry as immutable JSON-Schemas.
Data Model changes
The data model itself is almost the same and keeps all existing design principles.
| Property | VCDM 1.1 | VCDM 2.0 |
|---|---|---|
| @context | The first item must be https://www.w3.org/2018/credentials/v1. | The first item must be https://www.w3.org/ns/credentials/v2. |
| issuanceDate | Expresses the date and time when a credential becomes valid. | Renamed to validFrom. |
| expirationDate | Expresses the date and time when a credential ceases to be valid. | Renamed to validFrom. |
| issued | Was reserved but not used. | Not applied. |
New Media Type
The new media types application/vc+ld+json and application/vp+ld+json have been reserved for Verifiable Credential and Verifiable Presentation, respectively. These media types are intended to be used in conjunction with securing mechanisms and do not imply any particular securing mechanism. The media types may be processed as JSON-LD (ld+json) or as JSON (+json). The JSON processing rules have been clarified in the section of JSON processing. While securing mechanisms may define other media types, the data model should be treated as application/vc+ld+json or as application/vp+ld+json.