Internet Engineering Task Force (IETF)                      M. Ortseifen
Request for Comments: 7207                                   G. Dickfeld
Category: Informational                              Deutsche Bundesbank
ISSN: 2070-1721                                               April 2014

    A Uniform Resource Name (URN) Namespace for Eurosystem Messaging

Abstract

   This document defines and registers with IANA a Uniform Resource Name
   (URN) namespace for usage within messages standardized by the
   Eurosystem.  The URN namespace is managed by Deutsche Bundesbank,
   which is a member of the European System of Central Banks (ESCB).

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Not all documents
   approved by the IESG are a candidate for any level of Internet
   Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7207.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Namespace Considerations  . . . . . . . . . . . . . . . . . .   3
   3.  Community Considerations  . . . . . . . . . . . . . . . . . .   3
   4.  Registration Template for the Eurosystem URN Namespace  . . .   4
   5.  Example . . . . . . . . . . . . . . . . . . . . . . . . . . .   6
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
     7.1.  Registration of Formal URN Namespace 'eurosystem' . . . .   7
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   7
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   7
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   7

1.  Introduction

   The European System of Central Banks (ESCB) is composed of the
   European Central Bank (ECB) [ECB] and the national central banks
   (NCBs) of all 27 EU Member States (Article 107.01 of the Treaty) --
   whether they have adopted the Euro currency or not.  One central bank
   belonging to the ESCB is Deutsche Bundesbank [DBBK], which, for the
   purpose of this document, is acting on behalf of the ESCB.  The term
   Eurosystem is used to refer to the entity composed of the ECB and the
   NCBs of those member states that have adopted the Euro currency.  For
   further information on the tasks of the ESCB and the Eurosystem,
   please refer to the ECB web site ([ECB], [ESCB], [Eurosystem]).

   The ESCB provides the TARGET2 (Trans-European Automated Realtime
   Gross Settlement Express Transfer) system for market infrastructure;
   it is an interbank payment system for the real-time processing of
   cross-border transfers throughout the European Union.  In addition,
   the ESCB is currently implementing TARGET2-Securities, a future
   securities settlement platform that offers a new, harmonized and
   centralized method of settling securities in central bank money.  The
   TARGET2-Securities project was initiated by the Eurosystem as
   platform owner in 2006.  TARGET2-Securities is currently under
   development.  Four central banks of the Eurosystem -- Deutsche
   Bundesbank, Banque de France, Banca d'Italia, and Banco de Espana
   (4CB) -- are entrusted with the development and the operation of the
   platform.  For details, see [T2S_ECB] and [T2S_DBBK].

   The future users of TARGET2-Securities will communicate and exchange
   information with the platform via messages (a set of structured
   information) following the ISO 20022 Standard [ISO20022-RA].

   This document specifies and registers with IANA a URN Namespace for
   the Eurosystem, which will be populated initially by names for
   abstract and concrete entities used in TARGET2-Securities messaging,
   but may be used for similar purposes in the future.

2.  Namespace Considerations

   The goal of the requested namespace is to ensure the stability and
   uniqueness of the names of various items that are used within the
   messages exchanged between the Eurosystem and the users of
   TARGET2-Securities (or potentially, other future projects of the
   Eurosystem).

   It is essential that names of items (such as the XML schema
   describing the message itself) can be used to identify the resource
   even years after the message has been exchanged.  This context
   requires a new namespace owned by, and under the perpetual control
   of, the Eurosystem.

   The messaging context of the needed identifiers necessitates the
   usage of Uniform Resource Identifiers (URIs) as specified in Internet
   STD 66 [RFC3986].

   The persistent identifiers needed are protocol-independent resource
   names -- the same resource may exist in multiple physical locations,
   and thus be accessible via multiple URLs, but there's the need for a
   single abstract identifier as a handle (name) for it.

   Thus, the logical choice for the placement of such a namespace is the
   use of Uniform Resource Names (URNs), as defined by [RFC1737] and
   [RFC2141] (and its work-in-progress successor), by specifying a new
   URN Namespace [RFC3406] for the Eurosystem.

3.  Community Considerations

   The Eurosystem messages carrying the resource names are exchanged in
   IP networks.  Although the mass production use of the assigned URNs
   will be contained in messages carried in cryptographic digital
   envelopes or Virtual Private Networks, the message-related resources
   being persistently named need to be referred to and resolved in the
   public Internet.  The transparency requirements (needed for
   establishing and maintaining public trust into the subject financial
   transaction systems), open software development processes, and
   software deployment require the origin and authority for the URNs to
   be easily identified, and the URNs to be resolved on the public
   Internet.  URI references to the Eurosystem resources will be used in
   connection with identifiers drawn from previously standardized Formal
   URN Namespaces allocated to other international treaty organizations,

   and it is mandatory that the authority behind the new URNs be easily
   and clearly identified, and be at a perceived "equivalent" standards
   level, parallel to the existing ones.  Therefore, a mnemonic, Formal
   URN Namespace Identifier is needed for the intended purpose.

   Thus, this document specifies a "Formal URN Namespace" using the
   procedures laid down in RFC 3406 [RFC3406] (and incorporates some of
   the additional information under discussion for its work-in-progress
   successor into the registration template below).

   The requested URN Namespace Identifier (NID) is 'eurosystem'.

4.  Registration Template for the Eurosystem URN Namespace

   The registration template below makes references to Internet STD 66,
   RFC 3986 [RFC3986].

   Namespace ID:  eurosystem

   Scope / kind of named resources:
      Resources related to Eurosystem messaging.
      This namespace is reserved to the Eurosystem and its community.

   Registration Information:

      -  version number:  1

      -  date:  2014-02-18

   Declared registrant of the Namespace:

      -  Registering organization:
         Name: Deutsche Bundesbank (member of ESCB)
         Address:
         Wilhelm-Epstein-Strasse 14
         D-60431  Frankfurt
         Germany
         URI: http://www.bundesbank.de/

      -  Designated contact person:
         Name: Miriam Ortseifen
         Address:
         Deutsche Bundesbank
         Zentrale, T2- und T2S-Service-Management
         Wilhelm-Epstein-Strasse 14
         D-60431  Frankfurt am Main
         Germany
         Email: iso20022@bundesbank.de

   Declaration of syntactic structure of NSS part:

      The structure of the Namespace Specific String is a flat space of
      printable URI characters (<pchar>; see RFC 3986), with a
      preference for short letter-digit-period-hyphen-based strings.
      The NSS has no knowable structure outside of the context of the
      Eurosystem community internal resolver.

   Relevant ancillary documentation:

      None

   Conformance with URN Syntax:

      No special consideration.

   Rules for Lexical Equivalence of NSS part:

      No special consideration.

   Usage of query part:

      There is no support for query instructions or other components of
      the query part to be used in URI references to 'eurosystem' URNs.

   Usage of fragment part:

      The fragment part of URI references to 'eurosystem' URNs has no
      particular specified utility.

   Identifier uniqueness considerations:

      Identifiers are opaquely assigned by Eurosystem URN Registration
      that guarantees uniqueness.  This is simply achieved by reliably
      keeping track of already assigned names and comparing all new
      proposed names to the ones already present in the database.  If
      the name already has been assigned, a new one has to be proposed.

   Identifier persistence considerations:

      Assigned URNs will not be reused and will remain valid beyond the
      lifecycle of the referenced resources.  However, it should be
      noted that although the URNs remain valid, the status of the
      referenced resource may change.

   Process of identifier assignment:

      Names are granted by Eurosystem URN Registration via proprietary
      registration procedures.

      Future changes to the assignment methods may allow others to
      assign sub-spaces of the flat namespace, but again, this knowledge
      is only valid internally and should never be inferred or relied
      upon externally.

   Process of identifier resolution:

      Eurosystem URNs are resolved via URN resolvers run under
      Eurosystem responsibility.

      Initially, resolution service will be provided via a web page
      listing the assigned names and the related metadata of the named
      resources.

   Validation mechanism:

      None specified.

5.  Example

   The following example is listed for pedagogical reasons only; it is
   not guaranteed to become actually assigned.

      urn:eurosystem:xsd:reda.012.001.01

6.  Security Considerations

   Since the URNs in this namespace are opaque, there are no additional
   security considerations other than those normally associated with the
   use and resolution of URIs and URNs in general (see the Security
   Considerations in Internet STD 66 [RFC3986], RFC 2141 [RFC2141], and
   BCP 66 [RFC3406]).

   It is noted, however, that attempting to resolve a Eurosystem URN
   through a resolver other than the one provided by the Eurosystem is
   error prone.  In any case, it is not considered authoritative.

7.  IANA Considerations

7.1.  Registration of Formal URN Namespace 'eurosystem'

   IANA maintains the registry of URN Namespaces [IANA-URN] and has
   registered a new Formal URN Namespace with the NID 'eurosystem' as
   per BCP 66 [RFC3406], using the registration template given above in
   Section 4.

8.  Acknowledgements

   The authors would like to acknowledge the advice and constructive
   input received from Subramanian Moonesamy and Alfred Hoenes, as well
   as David Black and the IESG for Last Call comments that helped to
   improve this document.

9.  References

9.1.  Normative References

   [RFC2141]  Moats, R., "URN Syntax", RFC 2141, May 1997.

   [RFC3406]  Daigle, L., van Gulik, D., Iannella, R., and P. Faltstrom,
              "Uniform Resource Names (URN) Namespace Definition
              Mechanisms", BCP 66, RFC 3406, October 2002.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66, RFC
              3986, January 2005.

9.2.  Informative References

   [DBBK]     "Deutsche Bundesbank", <http://www.bundesbank.de/>.

   [ECB]      "European Central Bank", <http://www.ecb.int/>.

   [ESCB]     The European Central Bank, "ECB, ESCB and the Eurosystem",
              <http://www.ecb.int/ecb/orga/>.

   [Eurosystem]
              The European Central Bank, "The Eurosystem - The European
              System of Central Banks", ISBN 978-928990267-0, 2008,
              <http://www.ecb.int/pub/pdf/other/escb_en.pdf>.

   [IANA-URN] IANA, "Uniform Resource Names (URN) Namespaces",
              <http://www.iana.org/assignments/urn-namespaces/>.

   [ISO20022-RA]
              ISO 20022 Registration Authority, "ISO 20022 - Universal
              financial industry message scheme",
              <http://www.iso20022.org/>.

   [RFC1737]  Sollins, K. and L. Masinter, "Functional Requirements for
              Uniform Resource Names", RFC 1737, December 1994.

   [T2S_DBBK] Deutsche Bundesbank, "TARGET2-Securities",
              <http://www.bundesbank.de/Navigation/EN/
              Core_business_areas/Payment_systems/TARGET2_securities/
              target2_securities.html>.

   [T2S_ECB]  European Central Bank, "ECB: About T2S",
              <http://www.ecb.int/paym/t2s/about/about/html/
              index.en.html>.

Authors' Addresses

   Miriam Ortseifen
   Deutsche Bundesbank
   Wilhelm-Epstein-Strasse 14
   D-60431  Frankfurt
   Germany

   EMail: iso20022@bundesbank.de

   Gunnar Dickfeld
   Deutsche Bundesbank
   Wilhelm-Epstein-Strasse 14
   D-60431  Frankfurt
   Germany

   EMail: iso20022@bundesbank.de