DRAFT: CN credential standard

[meiersi-da]

Draft code for a CN credential standard built in a similar fashion to how the CN token standard is built. The CIP text for it has not yet been written. The high-level idea is that:

• The standard defines APIs for

  • creating and updating credentials in a registry (see the CredentialRegistry interface)
  • querying the credentials using an off-ledger API, which also supports filtering (see the OpenAPI spec)
  • fetching credential in Daml code (see the CredentialRecord interface)

• The SVs run a credential registry as part of their Amulet Name Service (see the AnsCredentialRegistry implementation of the interface)

  • SVs protect their resources by requiring a refresh of the credential records every 90 days. Thus the traffic for the refresh protects them from somebody spamming the ACS of the DSO party
  • That registry is also used to solve the off-ledger API discovery problem in token standard.

• Third-parties are welcome to run registries as well. Their off-ledger APIs can be discovered in the ANS registry from a self-published credential by their party with a well-known key.

• Concrete sets of claims for specific use-cases are defined as part of additional CIPs, as outlined in https://docs.google.com/presentation/d/1PXVwQU98dPo4hhIrXt1U5pAutWa4YUlvS61xIiBMhgc/edit?slide=id.g328343e708d_0_468#slide=id.g328343e708d_0_468

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