TAO -> SubTAO

Verifiable Accreditations from a TAO to a SubTAO.

A Trusted Accreditation Organisation (TAO) can extend trust further down the hierarchy by accrediting Sub-Trusted Accreditation Organisations (SubTAOs). These SubTAOs may then be authorised to issue further Verifiable Accreditations or Verifiable Attestations, subject to defined constraints.

The Verifiable Accreditation should include:

Field
Description
Example

Issuer

DID of the TAO

did:cheqd:testnet:a2b675de-33d0-4044-8183-0d74f210cceb

Subject

DID of the SubTAO that is being accredited

did:cheqd:testnet:e66a9416-d03e-4ced-95e3-07af16e25bc5

Credential Subject

A set of structured permissions around what credentials the SubTAO is accredited to issue, and in which jurisdiction.

See below

Terms of use

A set of policies setting out the scope of Trust Chain for Relying parties to validate against.

See below

Permissions

The credentialSubject section outlines what the SubTAO is accredited to do — including supported credential types, relevant schemas, and jurisdictional constraints.

"credentialSubject": {
    "id": "did:cheqd:testnet:e66a9416-d03e-4ced-95e3-07af16e25bc5",
    "accreditedFor": [
      {
        "schemaId": "did:cheqd:testnet:8ea036da-f340-480d-8952-f5561ea1763c/resources/b10146d7-0d0f-41e0-8ee3-c76db64890be",
        "types": [
          "VerifiableCredential",
          "VerifiableAccreditation",
          "VerifiableAttestation",
          "VerifiableAccreditationToAccredit"
        ],
        "limitJurisdiction": "https://publications.europa.eu/resource/authority/atu/FIN"
      }
    ]
  },

Whereby:

Field
Description

schemaId

Schema of the Verifiable Accreditation that the SubTAO is accredited to issue themselves

types

Types of Credential that the SubTAO is accredited to issue

limitJurisdiction

(Optional) Permission that the TAO can set to limit the jurisdictional scope of the credentials issued in the ecosystem

Policies

The termsOfUse field contains an AccreditationPolicy, which points back to both the parent accreditation and the original root authorisation. This maintains traceability through the full trust chain.

"termsOfUse": {
    "type": "AccreditationPolicy",
    "parentAccreditation": "did:cheqd:testnet:8ea036da-f340-480d-8952-f5561ea1763c/resources/18de60ec-bed1-42e5-980c-601c432bc60b",
    "rootAuthorisation": "did:cheqd:testnet:8ea036da-f340-480d-8952-f5561ea1763c/resources/18de60ec-bed1-42e5-980c-601c432bc60b"
  }

Whereby:

Field
Description

type

Must be AccreditationPolicy

parentAccreditation

The DID URL of the Accreditation issued by another TAO or the Root TAO to the TAO

rootAuthoroisation

The DID URL of the Root of Trust Verifiable Authorsation

Example of fully formed Accreditation

The example below shows a Verifiable Accreditation that is issued by an TAO to a SubTAO, granting permission to issue further accreditations under a defined schema and policy chain.

{
  "@context": [
    "https://www.w3.org/2018/credentials/v1",
    "https://schema.org/schema.jsonld",
    "https://veramo.io/contexts/profile/v1"
  ],
  "issuer": {
    "id": "did:cheqd:testnet:b003df6f-ec8e-48dd-9a2b-7011c5cf0a5e"
  },
  "type": [
    "VerifiableCredential",
    "VerifiableAccreditationToAccredit"
  ],
  "issuanceDate": "2024-08-07T02:08:30.000Z",
  "credentialSubject": {
    "accreditedFor": [
      {
        "schemaId": "https://resolver.cheqd.net/1.0/identifiers/did:cheqd:testnet:b003df6f-ec8e-48dd-9a2b-7011c5cf0a5e?resourceName=VerifiableAccreditation&resourceType=JSONSchemaValidator2020",
        "types": [
          "VerifiableCredential",
          "VerifiableAccreditation",
          "VerifiableAttestation",
          "VerifiableAccreditationToAccredit"
        ]
      }
    ],
    "id": "did:cheqd:testnet:6af412d7-2f04-4e12-a424-e6719db487ad"
  },
  "termsOfUse": {
    "type": "AccreditationPolicy",
    "parentAccreditation": "did:cheqd:testnet:8ea036da-f340-480d-8952-f5561ea1763c/resources/18de60ec-bed1-42e5-980c-601c432bc60b",
    "rootAuthorisation": "did:cheqd:testnet:8ea036da-f340-480d-8952-f5561ea1763c/resources/18de60ec-bed1-42e5-980c-601c432bc60b"
  },
  "proof": {
    "type": "JwtProof2020",
    "jwt": "eyJhbGciOiJFZERTQSIsInR5cCI6IkpXVCJ9.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.CrEirG-Yki2HCfY6GjNR_Oqx0ZV6uJr1NPpTTLnVWfG1Q9R3YASj7IyEZ3FtVGRmdSNhQ9v2pmPijVxeBnwPAg"
  }
}

For all Verifiable Accreditations, the accreditations are stored as DID-Linked Resources (DLRs), linked to the DID of the Accreditor. This means that the Accreditations are publically available, fully DID resolvable and are signed by the authentication keys within the DID Document of the Accreditor.

To issue a Verifiable Accreditation, follow the tutorial below:

Last updated

Was this helpful?