    Internet Engineering Task Force (IETF)                        P. Lemieux
    Request for Comments: 7972                       Sandflow Consulting LLC
    Obsoletes: 7302                                           September 2016
    Category: Informational
    ISSN: 2070-1721

       Entertainment Identifier Registry (EIDR) URN Namespace Definition

    Abstract

       Entertainment Identifier Registry (EIDR) Identifiers are used for the
       globally unique identification of motion picture and television
       content.  This document defines the formal Uniform Resource Name
       (URN) Namespace Identifier (NID) for EIDR Identifiers.

       This document obsoletes RFC 7302.

    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 7841.

       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/rfc7972.

    Copyright Notice

       Copyright (c) 2016 IETF Trust and the persons identified as the
       document authors.  All rights reserved.

       This document is subject to BCP 78 and the IETF Trust's Legal
       Provisions Relating to IETF Documents
       (http://trustee.ietf.org/license-info) in effect on the date of
       publication of this document.  Please review these documents
       carefully, as they describe your rights and restrictions with respect
       to this document.  Code Components extracted from this document must
       include Simplified BSD License text as described in Section 4.e of
       the Trust Legal Provisions and are provided without warranty as
       described in the Simplified BSD License.

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    RFC 7972              EIDR URN Namespace Definition       September 2016

    Table of Contents

       1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
       2.  Completed URN Namespace Definition Template . . . . . . . . .   3
       3.  Namespace Considerations  . . . . . . . . . . . . . . . . . .   7
       4.  Community Considerations  . . . . . . . . . . . . . . . . . .   7
       5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
       6.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
       7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
         7.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
         7.2.  Informative References  . . . . . . . . . . . . . . . . .   8
       Appendix A.  Summary of Changes (Informative) . . . . . . . . . .  10
         A.1.  Introduction  . . . . . . . . . . . . . . . . . . . . . .  10
         A.2.  Changes from RFC 7302 . . . . . . . . . . . . . . . . . .  10
       Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  10

    1.  Introduction

       This document defines the formal Uniform Resource Name (URN)
       Namespace Identifier (NID) for EIDR Identifiers.

       EIDR Identifiers are centrally registered, globally unique
       identifiers for audiovisual works and their variants, primarily film
       and television.  A unique set of metadata parameters describing the
       associated work is bound to the EIDR Identifier at the time of
       registration.

       EIDR Identifiers are a special kind of DOI Name allocated by EIDR
       Association specifically for audiovisual works.  The Digital Object
       Identifier (DOI) system provides an infrastructure for persistent
       unique identification of objects of any type and is specified in
       [ISO26234].  A DOI Name is the identifier that is permanently
       assigned to an object.  The use of DOI Names ensures persistence,
       global uniqueness, and an open resolution infrastructure.

       As a DOI Name, an EIDR Identifier has two components: a prefix
       assigned exclusively to EIDR Association by the DOI Registration
       Authority and a suffix defined by EIDR Association.  Currently, EIDR
       Identifiers use the prefix "10.5240", but additional prefixes might
       be introduced in the future.

       The following is an example of an EIDR Identifier in its canonical
       representation:

                       10.5240/7791-8534-2C23-9030-8610-5

       where "10.5240" is the prefix and "7791-8534-2C23-9030-8610-5" is the
       suffix.

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    RFC 7972              EIDR URN Namespace Definition       September 2016

       The canonical URN representation of the same EIDR Identifier is:

                       urn:eidr:10.5240:7791-8534-2C23-9030-8610-5

       Note that ":" is used as separator between the prefix and the suffix
       since "/" is a URN reserved character.

       [EIDR-OVERVIEW] and [EIDR-INTRO] provide additional background
       information.

       This document obsoletes RFC 7302.  See Appendix A for a summary of
       changes.

    2.  Completed URN Namespace Definition Template

       The namespace definition according to the template in [RFC3406] is as
       follows:

       Namespace ID:

          eidr

       Registration Information:

          Version 1

          2014-03-03

       Declared registrant of the namespace:

          Name:

             Entertainment Identifier Registry Association

          Address:

             c/o Alliances Management
             544 Hillside Road
             Redwood City, CA 94062
             USA

          Contact:

             URL: http://eidr.org/contact/
             Email: info@eidr.org

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    RFC 7972              EIDR URN Namespace Definition       September 2016

       Declaration of syntactic structure:

          An EIDR Identifier is a special kind of DOI Name (see [ISO26234])
          and, as such, consists of two components: a prefix denoted EIDR-
          PREFIX and a suffix denoted EIDR-SUFFIX.  The URN representation
          URN-EIDR of an EIDR Identifier conforms to the syntax (expressed
          using [RFC5234]):

                       URN-EIDR = "urn:eidr:" EIDR-NSS
                       EIDR-NSS = EIDR-PREFIX ":" EIDR-SUFFIX
                       EIDR-PREFIX = 1*EIDR-CHARS
                       EIDR-SUFFIX = 1*EIDR-CHARS
                       EIDR-CHARS = ALPHA / DIGIT / "-" / "." / "_"

          The only value of EIDR-PREFIX currently in use is "10.5240".
          Additional prefix values conforming to the EIDR-PREFIX syntax
          might be introduced by EIDR Association in the future.  In all
          cases, each of these additional prefix values will be associated
          with suffix values that conform to a subset of the EIDR-SUFFIX
          syntax.  These additional prefixes and their corresponding
          suffixes will be documented in future revisions to this
          registration.

          An implementation can process an EIDR-NSS with an unknown prefix
          as an opaque string per the "Rules of Lexical Equivalence" below,
          and resolve it as a generic DOI Name per the "Process for
          identifier resolution" below.

          When EIDR-PREFIX is equal to "10.5240", the syntax of EIDR-SUFFIX
          is further constrained according to the RP2079-SUFFIX syntax
          specified in [SMPTERP2079]:

                       RP2079-SUFFIX = 5(4HEXDIG "-") CHECK
                       CHECK         = DIGIT / ALPHA

          where CHECK is the Mod 37,36 check character as specified in
          [ISO7064], computed over the 20 hexadecimal digits HEXDIG of
          RP2079-SUFFIX.

          EXAMPLE: urn:eidr:10.5240:7791-8534-2C23-9030-8610-5

       Relevant ancillary documentation:

          [ISO26234] specifies DOI Name syntax and registration.

          [SMPTERP2079] specifies the syntax of the EIDR Identifier with the
          prefix "10.5240".

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    RFC 7972              EIDR URN Namespace Definition       September 2016

       Identifier uniqueness considerations:

          An EIDR Identifier is a DOI Name.  The ISO 26324 Registration
          Authority ensures DOI Name uniqueness; therefore, the URN-EIDR
          derived from an EIDR Identifier is guaranteed to be unique and
          never reassigned.

          Furthermore, an EIDR Identifier is associated with a single URN-
          EIDR.

       Identifier persistence considerations:

          An EIDR Identifier is a DOI Name.  The ISO 26324 Registration
          Authority ensures that a DOI Name remains valid indefinitely;
          therefore, the URN-EIDR derived from an EIDR Identifier remains
          valid indefinitely.

       Process of identifier assignment:

          EIDR Association registers each EIDR Identifier with the ISO 26324
          Registration Authority.

          Entities involved in the motion picture and television industry,
          either directly in the production of content or in its
          distribution and related services, are eligible to apply for
          registrant status.  Registrants pay an annual membership fee that
          depends on the size of the company.

       Process for identifier resolution:

          As a DOI Name, the resolution of the EIDR Identifier associated
          with an EIDR-NSS is handled by the ISO 26324 Registration
          Authority.

          The ISO 26324 Registration Authority operates a web service that
          allows the EIDR Identifier associated with an EIDR-NSS to be
          resolved by issuing an HTTP GET request to the following URI (see
          [RFC7231] and [RFC2818]):

                               "https://doi.org/" URN-EIDR

          If the EIDR Identifier exists, then an XML Schema instance
          document (see [XMLSchema]) containing metadata associated with the
          EIDR Identifier is returned; otherwise, the HTTP status code "404
          Not Found" is returned.

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    RFC 7972              EIDR URN Namespace Definition       September 2016

       EXAMPLE: https://doi.org/urn:eidr:10.5240:7791-8534-2C23-9030-8610-5

          NOTE: The web service uses the HTTP Accept header to determine the
          format of the response.  When using a web browser to access the
          resource above, the query string "?locatt=type:Full" is appended
          to the URI to explicitly request an XML response.

          EIDR Association operates additional services specifically
          tailored to EIDR users (see [EIDR-SERVICES] and [DOI-EIDR-PROXY]).
          These services include additional features, e.g., the ability to
          register EIDR Identifiers and web-based GUI tools.

       Rules for Lexical Equivalence:

          Lexical equivalence of the URN-EIDR is defined by case-insensitive
          string match.

          NOTE: The URN-EIDR includes the "urn:eidr:" string, as specified
          under "Declaration of syntactic structure".

       Conformance with URN Syntax:

          As specified above, the syntax of the URN-EIDR is a subset of the
          URN syntax specified in [RFC2141].

       Validation mechanism:

          The validity of an EIDR-NSS can only be guaranteed by completing
          the resolution process.

          For EIDR-NSS with an EIDR-PREFIX equal to "10.5240", the CHECK
          value can be used for integrity checking, as specified above.

       Scope:

          EIDR Identifiers are centrally registered, globally unique
          identifiers for use with audiovisual works worldwide.

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    RFC 7972              EIDR URN Namespace Definition       September 2016

    3.  Namespace Considerations

       EIDR Identifiers are intended for use in Internet applications, where
       URNs are routinely used to identify audiovisual resources.  There is
       no direct mapping from EIDR Identifiers to existing URN namespaces.

    4.  Community Considerations

       The primary registrants of EIDR Identifiers are producers and
       distributors of audiovisual works, metadata aggregators, and
       audiovisual archives.  Any bona fide member of the ecosystem can
       become an EIDR member and register any work.  EIDR Identifiers can be
       used by anyone to unambiguously identify an audiovisual asset and
       retrieve underlying metadata.  The primary benefits of their use are
       associated with works in wide distribution, management of long or
       complex distribution chains, and aggregation of information from
       multiple sources.

    5.  IANA Considerations

       IANA has registered the Formal URN Namespace 'eidr' in the "Uniform
       Resource Names (URN) Namespaces" registry, using the registration
       template in Section 2 of this document.

    6.  Security Considerations

       This document specifies the syntax of the URN-EIDR namespace and
       makes no security representations.  Furthermore, the details of
       assignment and resolution processes are defined external to this
       document by EIDR Association and the ISO 26324 Registration
       Authority, and are thus outside the scope of this document.  Note,
       however, that failure to conform to the syntactic and lexical
       equivalence rules in this specification when using an EIDR Identifier
       as a criteria for accessing restricted resources can result in
       granting unauthorized access to these resources.

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    RFC 7972              EIDR URN Namespace Definition       September 2016

    7.  References

    7.1.  Normative References

       [ISO26234] International Organization for Standardization (ISO), "ISO
                  26324:2012 Information and documentation -- Digital object
                  identifier system", ISO Standard 26324, June 2012.

       [ISO7064]  International Organization for Standardization,
                  "Information technology -- Security techniques -- Check
                  character systems", ISO Standard 7064, February 2003.

       [RFC2141]  Moats, R., "URN Syntax", RFC 2141, DOI 10.17487/RFC2141,
                  May 1997, <http://www.rfc-editor.org/info/rfc2141>.

       [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
                  Specifications: ABNF", STD 68, RFC 5234,
                  DOI 10.17487/RFC5234, January 2008,
                  <http://www.rfc-editor.org/info/rfc5234>.

       [SMPTERP2079]
                  Society of Motion Picture and Television Engineers,
                  "Digital Object Identifier (DOI) Name and Entertainment ID
                  Registry (EIDR) Identifier Representations",
                  DOI 10.5594/SMPTE.RP2079.2013, SMPTE RP 2079, 2014.

    7.2.  Informative References

       [DOI-EIDR-PROXY]
                  Entertainment Identifier Registry Association, "EIDR and
                  the DOI Proxy", May 2015,
                  <http://eidr.org/documents/EIDR_and_the_DOI_Proxy.pdf>.

       [EIDR-INTRO]
                  Entertainment Identifier Registry Association, "EIDR: ID
                  Format Ver. 1.1", August 2013,
                  <http://eidr.org/documents/EIDR_ID_Format_v1.1.pdf>.

       [EIDR-OVERVIEW]
                  Entertainment Identifier Registry Association, "EIDR
                  Overview", November 2013, <http://eidr.org/
                  documents/2013-11-01_EIDR_Overview_FINAL.pdf>.

       [EIDR-SERVICES]
                  Entertainment Identifier Registry Association, "EIDR
                  System Version 2.0: Registry User's Guide", August 2013,
                  <http://eidr.org/documents/
                  EIDR_2.0_Registry_User_Guide.pdf>.

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       [RFC2818]  Rescorla, E., "HTTP Over TLS", RFC 2818,
                  DOI 10.17487/RFC2818, May 2000,
                  <http://www.rfc-editor.org/info/rfc2818>.

       [RFC3406]  Daigle, L., van Gulik, D., Iannella, R., and P. Faltstrom,
                  "Uniform Resource Names (URN) Namespace Definition
                  Mechanisms", BCP 66, RFC 3406, DOI 10.17487/RFC3406,
                  October 2002, <http://www.rfc-editor.org/info/rfc3406>.

       [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
                  Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
                  DOI 10.17487/RFC7231, June 2014,
                  <http://www.rfc-editor.org/info/rfc7231>.

       [rfcdiff]  "Rfcdiff Tool", <https://tools.ietf.org/tools/rfcdiff/>.

       [XMLSchema]
                  Holstege, M. and A. Vedamuthu, "W3C XML Schema Definition
                  Language (XSD): Component Designators", W3C Candidate
                  Recommendation CR-xmlschema-ref-20100119, January 2010,
                  <http://www.w3.org/TR/2010/CR-xmlschema-ref-20100119>.

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    RFC 7972              EIDR URN Namespace Definition       September 2016

    Appendix A.  Summary of Changes (Informative)

    A.1.  Introduction

       This Appendix summarizes changes across revisions of this
       specification.  This summary is informative and not intended to be
       exhaustive.  Readers seeking a definitive list of changes are instead
       encouraged to use tools such as [rfcdiff].

    A.2.  Changes from RFC 7302

       o  "Process for identifier resolution" paragraph: The syntax for the
          URI supplied to the web service is modified to use (a) the 'https'
          scheme and (b) the URN-EIDR representation of the EIDR Identifier.

    Author's Address

       Pierre-Anthony Lemieux
       Sandflow Consulting LLC

       Email: pal@sandflow.com

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