OBB-FAPI-1-DCR-ID2 November 2021
Bragg & Security Standards Track [Page]
Workgroup:
Open Banking Brasil GT Security
Internet-Draft:
open-banking-brasil-dynamic-client-registration-1_ID2
Published:
Intended Status:
Standards Track
Authors:
R. Bragg
Raidiam
GT. Security
OBBIS

Open Banking Brasil Financial-grade API Dynamic Client Registration 1.0 Implementers Draft 2

Foreword

Este documento também está disponível em português

The Open Banking Brasil Initial Structure is responsible for creating standards and specifications necessary to meet the requirements and obligations of the Brasil Open Banking Legislation as originally outlined by the Brasil Central Bank. There is a possibility that some of the elements of this document may be the subject to patent rights. OBBIS shall not be held responsible for identifying any or all such patent rights.

Open Banking Brasil Financial-grade API Security Profile 1.0 consists of the following parts:

These parts are intended to be used with RFC6749, RFC6750, RFC7636, OIDC, OIDR, RFC7591, RFC7592, FAPI-1-Baseline and FAPI-1-Advanced

Introduction

The Open Banking Brasil Financial-grade API Dynamic Client Registration Profile is a profile of RFC7591, RFC7592 and OIDR that aims to provide specific implementation guidelines for security and interoperability which can be applied to the identification, registration and management of OAuth Clients operating in the Brasil Open Banking ecosystem. Although it is possible to code an OpenID Provider and Relying Party from first principles using this specification, the main audience for this specification is parties who already have a certified implementation of OpenID Connect and want to achieve certification for the Brasil Open Banking programme.

Notational Conventions

The key words "shall", "shall not", "should", "should not", "may", and "can" in this document are to be interpreted as described in ISO Directive Part 2. These key words are not used as dictionary terms such that any occurrence of them shall be interpreted as key words and are not to be interpreted with their natural language meanings.

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Table of Contents

1. Scope

This document specifies the method of

This document is applicable to all participants engaging in Open Banking in Brasil.

2. Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applied. For undated references, the latest edition of the referenced document (including any amendments) applies.

ISODIR2 - ISO/IEC Directives Part 2

RFC6749 - The OAuth 2.0 Authorization Framework

RFC6750 - The OAuth 2.0 Authorization Framework: Bearer Token Usage

RFC7636 - Proof Key for Code Exchange by OAuth Public Clients

RFC6819 - OAuth 2.0 Threat Model and Security Considerations

RFC7519 - JSON Web Token (JWT)

RFC7591 - OAuth 2.0 Dynamic Client Registration Protocol

RFC7592 - OAuth 2.0 Dynamic Client Registration Management Protocol

BCP195 - Recommendations for Secure Use of Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS)

OIDC - OpenID Connect Core 1.0 incorporating errata set 1

FAPI-CIBA - Financial-grade API: Client Initiated Backchannel Authentication Profile

RFC4514 - Lightweight Directory Access Protocol (LDAP): String Representation of Distinguished Names

OIDD - OpenID Connect Discovery 1.0 incorporating errata set 1

OIDR - OpenID Connect Registration 1.0 incorporating errata set 1

RFC8705 - OAuth 2.0 Mutual TLS Client Authentication and Certificate Bound Access Tokens

JARM - Financial-grade API: JWT Secured Authorization Response Mode for OAuth 2.0 (JARM)

PAR - OAuth 2.0 Pushed Authorization Requests

JAR - OAuth 2.0 JWT Secured Authorization Request

FAPI-1-Baseline - Financial-grade API Security Profile 1.0 - Part 1: Baseline

FAPI-1-Advanced - Financial-grade API Security Profile 1.0 - Part 2: Advanced

OBB-FAPI - Open Banking Brasil Financial-grade API Security Profile 1.0

OBB-Cert-Standards - Open Banking Brasil x.509 Certificate Standards

OBB-DCR/DCM-Swagger - DCR & DCM Swagger

3. Terms and definitions

For the purpose of this document, the terms defined in RFC6749, RFC6750, RFC7636, OpenID Connect Core and ISO29100 apply.

4. Symbols and Abbreviated terms

SSA - Software Statement Assertion

SS - Software Statement

DCR - Dynamic Client Registration

API - Application Programming Interface

FAPI - Financial-grade API

HTTP - Hyper Text Transfer Protocol

OIDF - OpenID Foundation

REST - Representational State Transfer

TLS - Transport Layer Security

5. Introduction

Brasil Open Bankings ecosystem leverages a federation trust provider or directory of participants as the golden source of information on accredited participants and software that are authorized to partake in the Open Banking Brasil ecosystem.

The services by the Directory include

Participants within the ecosystem must leverage these services to facilitate API driven OAuth client registration using the process outlined in clause 3.1.1 of RFC7591 with additional metadata necessary to support OpenID Connect defined in OpenID Connect Registration.

It's important to remember that the client registration payload has most of its non-mandatory attributes, and that assigned values; that conflict with the present in the assertion software declaration will be overridden by the values of the software statement assertion issued by the Directory of Participants. Not all metadata that a client wishes to provide may be contained in a software statement, e.g alternative Metadata Languages and Script values. There are some cases when the client metadata are subset os the existing values in the SSA, such as redirect_URIs.

6. Open Banking Brasil OpenID Connect Discovery provisions

6.1. Authorization server

The Authorization Server shall support OpenID Connect Discovery as required by Financial-grade API Security Profile 1.0 - Part 1: Baseline. This support shall be explicit in Participant Directory configurations, and in the declaration of its attributes in the Discovery file (well-known), respecting the authentication mechanisms certified by the institution through the Open Banking Brazil compliance tests.

In addition, the Authorization Server

  1. shall advertise its presence in the Open Banking Brasil ecosystem by being listed on the Directory of Participants;

  2. shall advertise all Open Banking Brasil REST API resources protected by the OpenID Provider on the Directory of Participants;

  3. shall advertise support for all signing, encryption, authentication mechanisms and standards required to support Open Banking Brasil Financial API;

  4. shall advertise support for OpenID Dynamic Client Registration;

  5. shall advertise mtls_endpoint_aliases as per clause 5 RFC 8705 OAuth 2.0 Mutual-TLS Client Authentication and Certificate-Bound Access Tokens the token_endpoint, registration_endpoint and userinfo_endpoint;

  6. if supporting OAuth 2.0 Pushed Authorization Requests shall advertise through OIDD mtls_endpoint_aliases the pushed_authorization_request_endpoint;

  7. if supporting Financial API - Client Initiated Back Channel Authentication shall advertise through OIDD mtls_endpoint_aliases the backchannel_authentication_endpoint;

6.2. Client

The Client shall support OpenID Connect Discovery as required by Financial-grade API Security Profile 1.0 - Part 1: Baseline

In addition, the Client

  1. shall rely on ecosystem discovery services provided by Directory of Participants only;

  2. shall derive necessary Authorisation Server metadata by relying on an Authorization Servers OpenID Connect Discovery services only;

  3. where present, shall use endpoints advertised in mtls_endpoint_aliases as per clause 5 RFC 8705 OAuth 2.0 Mutual-TLS Client Authentication and Certificate-Bound Access Tokens;

7. Open Banking Brasil OpenID Connect Registration Provisions

7.1. Authorization server

The Authorization Server shall support the RFC RFCs Dynamic Client Registration (DCR) RFC7591, Dynamic Client Management (DCM) RFC7592 and OpenID Registration

In addition, the Authorization Server

  1. shall reject dynamic client registration requests not performed over a connection secured with mutual tls using certificates issued by Brazil ICP (production) or the Directory of Participants (sandbox);

  2. shall validate that the request contains software_statement JWT signed using the PS256 algorithim issued by the Open Banking Brasil directory of participants;

  3. shall validate that the software_statement was issued (iat) not more than 5 minutes prior to the request being received;

  4. shall validate that the attribute jwks (key set by value) was not included; but declared as a reference in the jwks_uri attribute;

  5. when the jwks_uri was informed, shall validate that matches the software_jwks_uri provided in the software_statement;

  6. shall require and validate that redirect_uris match or contain a sub set of softwareredirecturis provided in the software_statement;

  7. shall require and validate that all client authentication mechanism adhere to the requirements defined in RFC7591 and RFC7592, validating the registration_access_token and using a secure connection, protected by certificate Issued from chain of certificates linked to ICP-Brasil;

  8. removed;

  9. shall validate that the requested scopes are adequate for accredited institutions and their regulatory roles and contained in the software_statement. The list of regulatory permissions and the corresponding scopes are described in the following sections;

  10. where possible, shall compare client metadata asserted by a client toward the metadata provided into software_statement, choosing the values present in the SSA with precedence;

  11. shall accept all x.500 AttributeType name strings defined in the Distinguished Name of the x.509 Certificate Profiles defined in Open Banking Brasil x.509 Certificate Standards;

  12. if supporting tls_client_auth client authentication mechanism as defined in RFC8705 shall only accept tls_client_auth_subject_dn as an indication of the certificate subject value as defined in clause 2.1.2 RFC8705;

These provisions apply equally to the processing of RFC7591, RFC7592 and OpenID Registration requests

7.1.1. Applying Server Defaults

Where properties of a DCR request are not included and are not mandatory in the specification the Authorisation Server shall apply client defaults in the following manner

  1. shall select and apply the encryption algorithm and cipher choice from the most recommended of the IANA cipher suites that is supported by the Authorisation Server;

  2. shall populate defaults from values within the software_statement assertion where possible;

  3. shall grant the client permission to the complete set of potential scopes based on the softwares regulatory permissions included in the software_statement;

7.1.2. Certificate Distinguished Name Parsing

Clause 3 of Lightweight Directory Access Protocol (LDAP): String Representation of Distinguished Names defines the mandatory OIDs whose AttributeType strings (descriptors) must be recognized by implementers. This mandatory list does not include several of the OIDs defined in Open Banking Brasil x.509 Certificate Standards nor is there a defined mechanism for Authorisation Servers to publish information regarding the format that they would expect a Dynamic Client Registration request that includes a tls_client_auth_subject_dn to be presented in.

To address this ambiguity, the Authorization Server must accept only the AttributeTypes name strings (descriptors) defined in the last paragraph of clause 3 RFC4514 in string format, it shall also accept in OID format, with their values in ASN.1, all the AttributeTypes defined in Distinguished Name Open Banking Brasil x.509 Certificate Standards or added by the Certificate Authority.

In case of non-compliance with these requirements, the Authorization Server shall reject the registration.

In terms of format, follow below how decoding should be done:

  • Start backwards, the order is reversed from what is entered.

  • Append each RDN (RelativeDistinguishedName) segment with a comma ','.

  • Use the RFC strings (CN, L, ST, O, OR, C, Street, DC, UID) with the value of their attributes in "printable string", ie human-readable + the OIDs of the attributes defined in this specification for use in Distinguished Name Open Banking Brasil x.509 Certificate Standards (businessCategory=OID 2.5.4.15,jurisdictionCountryName=OID: 1.3.6.1.4.1.311.60.2.1.3, serialNumber=OID:2.5.4.5) with the value of your attributes in ASN.1 format.

Examples:

Table 1
subject_dn Issuer
UID=67c57882-043b-11ec-9a03-0242ac130003, 1.3.6.1.4.1.311.60.2.1.3=#13024252, 2.5.4.15=#131450726976617465204f7267616e697a6174696f6e, 2.5.4.5=#130d31333335333233363030313839, CN= mycn.bank.gov.br,OU=497e1ffe-b2a2-4a4e-8ef0-70633fd11b59, O=My Public Bank, L= BRASILIA, ST=DF, C=BR issuer=CN=Open Banking SANDBOX Issuing CA - G1,OU=Open Banking,O=Open Banking Brasil,C=BR
UID=67c57882-043b-11ec-9a03-0242ac130003, 1.3.6.1.4.1.311.60.2.1.3=#13024252, 2.5.4.15=#131450726976617465204f7267616e697a6174696f6e, CN=mycn.bank.gov.br, 2.5.4.5=#130d31333335333233363030313839, OU=497e1ffe-b2a2-4a4e-8ef0-70633fd11b59, O=My Public Bank, L=BRASILIA, ST=DF, C=BR issuer=CN=Autoridade Certificadora do SERPRO SSLv1,OU=Autoridade Certificadora Raiz Brasileira v10,O=ICP-Brasil,C=BR
1.3.6.1.4.1.311.60.2.1.3=#13024252, 2.5.4.15=#131450726976617465204f7267616e697a6174696f6e, UID=67c57882-043b-11ec-9a03-0242ac130003, CN=openbanking.mybank.com.br, 2.5.4.5=#130d31333335333233363030313839, OU=497e1ffe-b2a2-4a4e-8ef0-70633fd11b59, L=Goiania, ST=GO, O=MyBank SA, C=BR issuer=CN=AC SOLUTI SSL EV,OU=Autoridade Certificadora Raiz Brasileira v10,O=ICP-Brasil,C=BR
CN=mycn.bank.com.br, UID=67c57882-043b-11ec-9a03-0242ac130003, OU=497e1ffe-b2a2-4a4e-8ef0-70633fd11b59, L=Sao Paulo, ST=SP, O=MyBank SA, C=BR,2.5.4.5=#130d31333335333233363030313839, 1.3.6.1.4.1.311.60.2.1.3=#13024252, 2.5.4.15=#131450726976617465204f7267616e697a6174696f6e issuer=CN=AC SERASA SSL EV,OU=Autoridade Certificadora Raiz Brasileira v10,O=ICP-Brasil,C=BR

7.2. Regulatory Roles to OpenID and OAuth 2.0 Mappings

To participate in the Open Banking ecosystem, accredited institutions must register themselves in the directory of participants according to their regulatory roles. Those roles reflect the institutions' authorization from the Central Bank and, consequently, the APIs they are allowed to use.

The following table describes the regulatory roles for Open Banking and the related OAuth 2.0 scopes mapping. If the scopes are omitted during the DCR process, the authorization server shall grant the complete set of potential scopes based on the registering bank's regulatory roles, as described in the Server Defaults section.

Table 2
Regulatory Role Description Allowed Scopes Target Phase
DADOS Instituição transmissora ou receptora de dados (AISP) openid accounts credit-cards-accounts consents customers invoice-financings financings loans unarranged-accounts-overdraft resources Phase 2
PAGTO Instituição prestadora de serviço de iniciação de pagamentos (PISP) openid payments Phase 3
CONTA Instituição detentora de conta (ASPSP) openid Phase 3
CCORR Correspondente de crédito openid Phase 3*

7.2.1. Implementers Note

In line with guidance from the IETF and the direction of travel for fine-grained consent management. The obligation falls to the Authorisation Server to ensure that there is sufficient scope conveyed in an access token necessary to fulfill the Permissions conveyed in the Consent Request. This principle and requirement is reflected in the forthcoming Grant Management API.

7.3. Regulatory Roles to dynamic OAuth 2.0 scope Mappings

Table 3
Regulatory Role Allowed Scopes
DADOS consent:{ConsentId}
PAGTO consent:{ConsentId}

8. Software Statement

A software statement is a JSON Web Token (JWT) RFC7519 that asserts metadata values about the client software as a bundle.

8.1. Software Statement Claims

The following example contains all of the claims currently included in a software statement

{
  "software_mode": "Live",
  "software_redirect_uris": [
    "https://www.raidiam.com/accounting/cb"
  ],
  "software_statement_roles": [
    {
      "role": "DADOS",
      "authorisation_domain": "Open Banking",
      "status": "Active"
    },
    {
      "role": "PAGTO",
      "authorisation_domain": "Open Banking",
      "status": "Active"
    }
  ],
  "software_client_name": "Raidiam Accounting",
  "org_status": "Active",
  "software_client_id": "Cki1EbvjwyhPB12NGLlz2",
  "iss": "Open Banking Open Banking Brasil prod SSA issuer",
  "software_tos_uri": "https://www.raidiam.com/accounting/tos.html",
  "software_client_description": "Raidiam Accounting leverage cutting edge open banking access to bring you real time up to date views of your finances",
  "software_jwks_uri": "https://keystore.directory.openbankingbrasil.org.br/b961c4eb-509d-4edf-afeb-35642b38185d/25556d5a-b9dd-4e27-aa1a-cce732fe74de/application.jwks",
  "software_policy_uri": "https://www.raidiam.com/accounting/policy.html",
  "software_id": "25556d5a-b9dd-4e27-aa1a-cce732fe74de",
  "software_client_uri": "https://www.raidiam.com/accounting.html",
  "software_jwks_inactive_uri": "https://keystore.directory.openbankingbrasil.org.br/b961c4eb-509d-4edf-afeb-35642b38185d/25556d5a-b9dd-4e27-aa1a-cce732fe74de/inactive/application.jwks",
  "software_jwks_transport_inactive_uri": "https://keystore.directory.openbankingbrasil.org.br/b961c4eb-509d-4edf-afeb-35642b38185d/25556d5a-b9dd-4e27-aa1a-cce732fe74de/inactive/transport.jwks",
  "software_jwks_transport_uri": "https://keystore.directory.openbankingbrasil.org.br/b961c4eb-509d-4edf-afeb-35642b38185d/25556d5a-b9dd-4e27-aa1a-cce732fe74de/transport.jwks",
  "software_logo_uri": "https://www.raidiam.com/accounting/logo.png",
  "org_id": "b961c4eb-509d-4edf-afeb-35642b38185d",
  "org_number": "112233445566",
  "software_environment": "production",
  "software_version": "1.1",
  "software_roles": [
    "DADOS",
    "PAGTO"
  ],
  "org_name": "Open Banking Brasil",
  "iat": 1620060821,
  "organisation_competent_authority_claims": [
    {
      "authorisation_domain": "Open Banking",
      "authorisations": [],
      "registration_id": "13353236-OBB-CONTA",
      "authority_id": "687a1c94-b360-4e04-9589-0fa5cb16451b",
      "authority_name": "Banco Central",
      "authorisation_role": "CONTA",
      "authority_code": "BCB",
      "status": "Active"
    },
    {
      "authorisation_domain": "Open Banking",
      "authorisations": [],
      "registration_id": "13353236-OBB-DADOS",
      "authority_id": "687a1c94-b360-4e04-9589-0fa5cb16451b",
      "authority_name": "Banco Central",
      "authorisation_role": "DADOS",
      "authority_code": "BCB",
      "status": "Active"
    },
    {
      "authorisation_domain": "Open Banking",
      "authorisations": [],
      "registration_id": "13353236-OBB-PAGTO",
      "authority_id": "687a1c94-b360-4e04-9589-0fa5cb16451b",
      "authority_name": "Banco Central",
      "authorisation_role": "PAGTO",
      "authority_code": "BCB",
      "status": "Active"
    }
  ]
}

9. Dynamic Client Registration Request Processing

Dynamic Client Registration Request Processing

9.1. Posting a request with a software statement

This example includes various optional fields, some of which may not be applicable to some deployments. For a complete guide to the attributes and their requirements, consult the Swagger DCR/DCM link: OBB-DCR/DCM-Swagger . Line wraps within values are for display purposes only.

POST /reg HTTP/1.1
Host: auth.raidiam.com
Content-Type: application/json
{
"application_type": "web",
"grant_types": [
    "client_credentials",
    "authorization_code",
    "refresh_token",
    "implicit"
],
"id_token_signed_response_alg": "PS256",
"require_auth_time": false,
"response_types": [
    "code id_token",
    "id_token"
],
"software_statement": "eyJraWQiOiJzaWduZXIiLCJ0eXAiOiJKV1QiLCJhbGciOiJQUzI1NiJ9.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.W6hUAYhjT6I61rxEIVMKYKre93LTbRdzKnk9dJvUdzVgAz5B9KxZNutf27oO3k0hrjYVWBdWq23o_e4Y_AaKdpS9-rtU84JiHtmqV0wcFYIM8nqcUVWqQ-Ux6Nq9L2G-s2YNd3PcJ1e3yGg9h8553Gr7iJusKEgApzXUpkM2rBELQuumktUE_JBiuIkXmWxoRnO1cW-Osbk3MT3bxG43SPcxii07Q5S8qXI6PjCPA3fYlnaUAygwZM3O0oa7jqmSr7d9UsHuDMJfYhIKdq2wyQQKORCN-D2UopmMX-lHMvAVkkrAO08T0-7odjr4PJk-PrwuoCxeAfa7440ZDOrlmQ",
"subject_type": "public",
"token_endpoint_auth_method": "private_key_jwt",
"introspection_endpoint_auth_method": "private_key_jwt",
"revocation_endpoint_auth_method": "private_key_jwt",
"request_object_signing_alg": "PS256",
"require_signed_request_object": true,
"require_pushed_authorization_requests": false,
"tls_client_certificate_bound_access_tokens": true,
"client_id": "aCnBHjZBvD6ku3KVBaslL",
"client_name": "Raidiam Accounting",
"client_uri": "https://www.raidiam.com/accounting.html",
"request_object_encryption_alg": "RSA-OAEP",
"request_object_encryption_enc": "A256GCM"
"jwks_uri": "https://keystore.directory.openbankingbrasil.org.br/b961c4eb-509d-4edf-afeb-35642b38185d/25556d5a-b9dd-4e27-aa1a-cce732fe74de/application.jwks",
"redirect_uris": [
    "https://www.raidiam.com/accounting/cb"
]
}

9.3. About authentication and authorization mechanisms for DCR and DCM services

As they are auxiliary services to the main flow of Open Banking Brasil, the dynamic registration and maintenance services for clients cannot use the exact access control mechanisms. For example, it is not possible to require an OAuth 2.0 access_token from a client application that isn't registered yet with the transmitting institution.

To extend RFC7591 and RFC7592, which recommend minimum mechanisms for authentication of their services, institutions that support the registration flows and dynamic maintenance of clients must implement the following controls:

9.3.1. Client registration - POST /register

  1. validate that the certificate presented by the client application is subordinate to the ICP-Brasil chains defined in the Open Banking Brasil Certificates Standard;

  2. ensure that the signature of the software_statement_ presented by the client application during registration has been made by the Directory of Participants using the public keys described in the previous section;

  3. ensure that the software_statement presented by the client application during registration corresponds to the same institution as the client certificate presented, validating it through the attributes that bring organization_id in the X.509 certificate.

9.3.2. Client Maintenance - GET /register - PUT /register - DELETE /register

  1. validate that the certificate presented by the client application is subordinate to the ICP-Brasil chains defined in the Open Banking Brasil Certificates Standard;

  2. Validate the presence and matching of the Bearer header Authorization containing the value of the registration_access_token attribute returned during registration of the corresponding client.

10. Acknowledgement

With thanks to all who have set the foundations for secure and safe data sharing through the formation of the OpenID Foundation FAPI Working Group, the Open Banking Brasil GT Security and to the pioneers who will stand on their shoulders.

The following people contributed to this document:

Appendix A. Notices

Copyright (c) 2021 Open Banking Brasil Initial Structure.

The Open Banking Brasil Initial Structure (OBBIS) grants to any Contributor, developer, implementer, or other interested party a non-exclusive, royalty-free, worldwide copyright license to reproduce, prepare derivative works from, distribute, perform and display, this Implementers Draft or Final Specification solely for the purposes of (i) developing specifications, and (ii) implementing Implementers Drafts and Final Specifications based on such documents, provided that attribution be made to the OBBIS as the source of the material, but that such attribution does not indicate an endorsement by the OBBIS.

The technology described in this specification was made available from contributions from various sources, including members of the OpenID Foundation, the Open Banking Brasil GT Security Working Group and others. Although the Open Banking Brasil Initial Structure has taken steps to help ensure that the technology is available for distribution, it takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this specification or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any independent effort to identify any such rights. The Open Banking Brasil Initial Structure and the contributors to this specification make no (and hereby expressly disclaim any) warranties (express, implied, or otherwise), including implied warranties of merchantability, non-infringement, fitness for a particular purpose, or title, related to this specification, and the entire risk as to implementing this specification is assumed by the implementer. The Open Banking Brasil Intellectual Property Rights policy requires contributors to offer a patent promise not to assert certain patent claims against other contributors and against implementers. The Open Banking Brasil Initial Structure invites any interested party to bring to its attention any copyrights, patents, patent applications, or other proprietary rights that may cover technology that may be required to practice this specification.

A.1. Appendix A. Example Software Statement Assertion 

eyJraWQiOiJzaWduZXIiLCJ0eXAiOiJKV1QiLCJhbGciOiJQUzI1NiJ9.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.W6hUAYhjT6I61rxEIVMKYKre93LTbRdzKnk9dJvUdzVgAz5B9KxZNutf27oO3k0hrjYVWBdWq23o_e4Y_AaKdpS9-rtU84JiHtmqV0wcFYIM8nqcUVWqQ-Ux6Nq9L2G-s2YNd3PcJ1e3yGg9h8553Gr7iJusKEgApzXUpkM2rBELQuumktUE_JBiuIkXmWxoRnO1cW-Osbk3MT3bxG43SPcxii07Q5S8qXI6PjCPA3fYlnaUAygwZM3O0oa7jqmSr7d9UsHuDMJfYhIKdq2wyQQKORCN-D2UopmMX-lHMvAVkkrAO08T0-7odjr4PJk-PrwuoCxeAfa7440ZDOrlmQ

Authors' Addresses

Ralph Bragg
Raidiam
URI: https://www.raidiam.com/
OBBIS GT Security
Open Banking Brasil Initial Structure
URI: https://openbankingbrasil.org.br/