CX-0167 BPN-DID Resolution v.1.0.0
ABSTRACT
This standard specifies the BPNBPN A BPN is the unique identifier of a partner within Catena-X.-DID Resolution Service (BDRS) as central core service that provides mapping information between companies BPNBPN A BPN is the unique identifier of a partner within Catena-X.-Ls and the matching DID under which they are reachable within the Catena-X dataspace
FOR WHOM IS THE STANDARD DESIGNED
The standard is designed for everybody who wants to understand the process of how a Data Consumer can get access to the offerings of a Data Provider based on the company name of the Data Provider. The mechanism described in this standard is part of this journey. Further steps are described in CX-0018.
1 INTRODUCTION
1.1 AUDIENCE & SCOPE
This section is non-normative
For certification:
- Core Service Provider-B - This role must certify against the standard
For implementation:
- Business Application Providers
- Enablement Service Providers
1.2 CONTEXT AND ARCHITECTURE FIT
This section is non-normative
The following diagram shows a deployment view of the BDRS service embedded into the relevant dataspace components:
The BDRS service is classified as Core Service-B. Itsdata is managed by other Core Services-B like the Registration
Orchestration Service for new Data Consumer/Provider. The service provides the BDRS Directory API which
allows access to the mapping data.
BDRS clients are operated by Enablement Service or Business Application Providers as part of their service architecture. BDRS clients are used by Data Consumers to initiate the technical process of a data transfer
The client uses the BDRS Directory API to synchronize the whole mapping data into the local environment, so that
they can be used for local request without exposing concrete information about data transfer partners outside of
its execution context.
BDRS clients, thereby can be a standalone service instance, but are typically a component in an existing service. E.g., the Eclipse Tractus-X EDCTractus-X EDC The Tractus-X Eclipse Dataspace Connector (Tractus-X EDC) is a reference implementation for a connector conformant to CX-0018 and acts as a de-facto standard/reference implementation within Catena-X; other CX-0018-conformant connectors are also valid options., the reference implementation of a participant agent (see CX-0018) contains a BDRS client and provides higher level APIsAPI An API is a way for two or more computer programs to communicate with each other., that integrate BDRS calls into the general discovery functionality.
1.3 CONFORMANCE AND PROOF OF CONFORMITY
This section is non-normative
As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.
The key words MAY, MUST, MUST NOT, OPTIONAL, RECOMMENDED, REQUIRED, SHOULD and SHOULD NOT in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.
Certification for this standard is only required for a Core Service Provider-B, as this role has to provide evidence of a working solution. All other roles may use the provided apiAPI An API is a way for two or more computer programs to communicate with each other., but do not have to certify against this standard. As it is an APIAPI An API is a way for two or more computer programs to communicate with each other. specification, the conformance has to be proven by the execution of test cases described in the CACs of this standard.
1.4 TERMINOLOGY
This section is non-normative
The following terms are used within the normative section of the standard
- BPNBPN A BPN is the unique identifier of a partner within Catena-X.-L: The Business Partner Number of the legal entity as defined in CX-0010
- DID: The DID of the legal entity used to participate in the Catena-X dataspace. The DID is defined in CX-0049
- Onboarding: The process under which a company becomes member of the Catena-X dataspace.
- BPNBPN A BPN is the unique identifier of a partner within Catena-X.-DID Resolution Service: The service defined by this standard.
- BDRS: Commonly used abbreviation for the BpnBPN A BPN is the unique identifier of a partner within Catena-X.-Did Resolution Service
- Core Service-B: A service that can only be executed once in a dataspace to provide seed functionality needed to operate the dataspace
- Core Service Provider-B: The service provider role for Core Services-B
- Enablement Service Provider: The role responsible to execute basic network services for a Data Provider/Consumer
- Business Application Provider: The role responsible for the execution of a business application that supports a certain use case within the Catena-X dataspace for a Data Provider/Consumer
- Data Consumer: The consuming dataspace participant acting as Data Provider/Consumer
- Data Provider: The providing dataspace participant acting as Data Provider/Consumer
- Verifiable Presentation: A cryptographic artefact, that contains Verifiable Credentials of the holder, signed by the holder of the credentials, see CX-0050
- Catena-X Membership Credential: The Verifiable Credential issued by the Core Service Provider-B to provide evidence concerning the membership in the Catena-X dataspace by the holder, see CX-0050
2 MAIN CONTENT
This section is normative
The BPN-DID Resolution Service (short BDRS) is a Core Service-B that MUST be provided by the Core Service Provider-B. It
offers mapping information between the BPNBPN A BPN is the unique identifier of a partner within Catena-X.-L and the corresponding DID of a legal entity. This is needed a Data Consumer to
initiate the technical process of a data transfer in cases where only the BPNBPN A BPN is the unique identifier of a partner within Catena-X.-L of the Data Provider is known.
The Core Service Provider-B MUST keep the service data up-to-date, i.e., if companies are onboarded or leave the dataspace, the corresponding mapping MUST be added/removed from the service data. The mechanism to maintain the data is out-of-scope for this standard.
The BDRS service is used by BDRS client apps. A BDRS client app MUST synchronize the complete mapping data and
act as local storage for the mapping data. The app MUST provide access to single mappings to consumers that need a concrete mapping.
The mechanism to access a single mapping is out-of-scope for this standard.x
The BDRS service MUST exclusively provide mapping data for onboarded legal entites referenced by their BPNBPN A BPN is the unique identifier of a partner within Catena-X.-Ls (as
defined in CX-0010). The mapped DIDs MUST furthermore follow the requirements of
CX-0049 and they MUST be the DIDs used or created during the Onboarding Process of the corresponding legal entity,
see CX-0006.
2.1 Retrieving the mapping information from the BDRS
A BDRS service MUST provide an endpoint that allows to retrieve all known mappings at once in a GZipped binary stream. This endpoint
is used by BDRS client apps to retrieve the mapping data.
The endpoint specification is described in this OpenApi spec.
Authentication
The access to the defined endpoint is protected by the Membership Credential. For authentication and authorization
purposes, a service implementation of the relevant endpoint MUST accept a bearer token in the Authorization header
with the following properties:
- The token MUST be a Verifiable Presentation that contains the Catena-X Membership Credential as defined in CX-0050.
The BDRS service MUST check the validity of the provided Membership Credential, e.g., correct type, not expired,
not revoked, properly signed by a trusted issuer. If validity check fails, access to the mapping data MUST be denied.
3 REFERENCES
3.1 NORMATIVE REFERENCES
Onboarding Process
Business Partner Number
DID Document
CX-Specific Credentials
3.2 NON-NORMATIVE REFERENCES
This section is non-normative
Dataspace Connectivity
3.3 REFERENCE IMPLEMENTATIONS
This section is non-normative
- In the bpn-did-resolution-service repository of Eclipse Tractus-X, you find a reference implementation for this standard.
- In the tractusx-edc repository, a BDRS client implementation is available. The component is implemented as an EDC extension
ANNEXES
FIGURES
This section is non-normative
- Figure 1: The deployment architecture of the BDRS service network
- Figure 2: The OpenAPI Spec of the BDRS Directory APIAPI An API is a way for two or more computer programs to communicate with each other.
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