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RFC 5119 - A Uniform Resource Name (URN) Namespace for the Socie

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Network Working Group                                         T. Edwards
Request for Comments: 5119                                           FOX
Category: Informational                                    February 2008

              A Uniform Resource Name (URN) Namespace for
     the Society of Motion Picture and Television Engineers (SMPTE)

Status of This Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.


   This document describes a Uniform Resource Name (URN) namespace for
   the Society of Motion Picture and Television Engineers (SMPTE) for
   naming persistent resources that SMPTE produces or manages.  A
   subnamespace for Universal Labels is specifically described.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  2
   2.  URN Namespace Definition Template  . . . . . . . . . . . . . .  2
   3.  Examples . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
   4.  Security Considerations  . . . . . . . . . . . . . . . . . . .  6
   5.  Namespace Considerations and Community Considerations  . . . .  6
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  7
   7.  SMPTE Registration Authority (Informative) . . . . . . . . . .  7
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . .  7
     8.1.  Normative References . . . . . . . . . . . . . . . . . . .  7
     8.2.  Informative References . . . . . . . . . . . . . . . . . .  7

1.  Introduction

   SMPTE (the Society of Motion Picture and Television Engineers) is an
   internationally-recognized standards-developing organization.
   Headquartered and incorporated in the United States of America, SMPTE
   has members in over 80 countries on six continents.  SMPTE's
   Engineering Documents, including Standards, Recommended Practices,
   and Engineering Guidelines, are prepared by SMPTE's Technology
   Committees.  Participation in these Committees is open to all with a
   bona fide interest in a committee's work.  SMPTE cooperates closely
   with other standards-developing organizations, including ISO, the
   IEC, and the ITU.  Also, the SMPTE Registration Authority maintains a
   registry of Universal Labels (ULs) used in identifying the type and
   encoding of data within data streams associated with audio-visual

   SMPTE would like to assign unique, permanent, and location-
   independent names using URNs for resources that SMPTE produces or

   This namespace specification is for a formal namespace.

2.  URN Namespace Definition Template

   The following template is provided in accordance with [RFC3406].

      Namespace ID:


      Registration Information:

         Version: 2

         Date: 2007-07-08

      Declared registrant of the namespace:

         Registering Organization: Society of Motion Picture and
                                   Television Engineers

            Address: 3 Barker Avenue - 5th Floor
                     White Plains, NY 10601 USA

         Designated Contact Person: Director of Engineering

            Phone: +1 (914) 761-1100
            Email: standards@smpte.org

      Declaration of structure:

         The Namespace Specific String (NSS) of all URNs that use the
         "smpte" NID shall be conformant to the URN syntax requirements
         defined in [RFC2141].

         URNs for the "urn:smpte" namespace shall follow the structure
         defined in [SMPTE2029].

         SMPTE (or it successor) may add additional subnamespaces
         in the future.  Any system that deals with URNs for the
         "urn:smpte" namespace should be written with the awareness
         that this could occur at any time.

         For informative purposes, the identifier structure described
         using ABNF (according to [RFC4234]) is as follows:

            ;start ABNF notation

            URN = "urn:" NID NSS

            NID = "smpte:"

            NSS = UL-NSS / other-NSS

            UL-NSS = "ul:" UL


            DOT = %x2E ; period

            QUADBYTE = 4BYTE

            BYTE = 2HEXDIG

            other-NSS = 1*(DIGIT / ALPHA / "-"/":")

            ; other-NSS that conforms with [RFC2141] for future

            ;end ABNF notation

      Relevant ancillary documentation:

         The structure for URNs in the "urn:smpte" namespace are defined
         in [SMPTE2029].

         The values of ULs in the "urn:smpte:ul" subnamespace shall be
         constrained as defined in [SMPTE298M].  Details regarding the
         use of ULs as keys in key-length-value (KLV) coding, including
         how to determine in which SMPTE registry a SMPTE-administered
         UL may be found, are described in [SMPTE336M].

      Identifier uniqueness considerations:

         [SMPTE2029] states that "All URNs in the SMPTE namespace shall
         conform to IETF RFC 3406.  In particular, URNs in the SMPTE
         namespace shall not be re-assigned, and URNs shall continue to
         be valid, even if the owners or registrants of the SMPTE
         resources identified by the URNs are no longer members or
         customers of SMPTE.  There need not be resolution of such URNs,
         but they shall not resolve to false or stale information."

         Additionally, the rules for assignment of SMPTE-administered
         ULs requires that each UL be unique to the UL space and that it
         cannot be reassigned or reused.

         It should be noted that [SMPTE298M] states that "A universal
         label shall be an 'object identifier' as specified by ISO/IEC
         8824-1," ([ISO8824-1]) although the SMPTE Universal Label
         representation is a specialized one that carries additional
         semantics over the OID representation of a URN OID ([RFC3061]).

         SMPTE will work to ensure that all current and future
         "urn:smpte" subnamespaces contain unique identifiers.

      Identifier persistence considerations:

         SMPTE-administered ULs may occasionally be deleted through
         SMPTE procedures.  Regardless, even after a UL has been
         deleted, it will not be reused.  Revisions to ULs will result
         in the creation of a new UL and the deletion of the old one.

         The persistence of URNs in future "urn:smpte" subnamespaces
         will be defined by SMPTE Standards.

      Process of identifier assignment:

         Assignment of URNs in the SMPTE NID is limited to SMPTE and
         those authorities that are specifically designated by SMPTE.
         SMPTE may designate portions of its namespace for assignment by
         other parties.

         Due process is followed by committees in the development of
         SMPTE documents.  Some types of Universal Label registrations
         and other registrations may require a fee to be paid to SMPTE.

         All classes of SMPTE-administered ULs require for registration
         the name and address of the applicant.  Some classes of labels
         also require the submission of supporting technical
         documentation for the label and may require a due process
         evaluation through the SMPTE Engineering Committee process.

      Process for identifier resolution:

         SMPTE-administered ULs are resolved through publications of the
         SMPTE Registration Authority.  Currently, publication of
         SMPTE-administered ULs are made through a Metadata Dictionary
         as specified in [RP210] and through the SMPTE Labels Registry
         as specified in [RP224], both of which are currently available
         online at http://www.smpte-ra.org/mdd/.

         SMPTE expects to develop and maintain "URN catalogs" that map
         all future assigned URNs in the "urn:smpte" namespace to
         Uniform Resource Locators (URLs) to enable Web-based resolution
         of named resources.

      Rules for Lexical Equivalence:

         Lexical equivalence of URNs in the "urn:smpte:ul" subnamespace
         is defined by case-insensitive string match.

         Lexical equivalence of URNs in additional subnamespaces of
         "urn:smpte:" will be specified by SMPTE in the defining
         document; in the absence of such specification, lexical
         equivalence of URNs in the "urn:smpte:" namespace outside of
         the "urn:smpte:ul" subnamespace is defined by exact string
         match, according to [RFC2141].

      Conformance with URN Syntax:

         No special considerations beyond the syntax herein described.

      Validation mechanism:




3.  Examples

   Currently, only a "urn:smpte:ul" subnamespace is defined.  This is
   the subnamespace for SMPTE Universal Labels [SMPTE298M].  SMPTE may
   add additional subnamespaces in the future.

   The following examples are not guaranteed to be real and are provided
   for illustrative purposes only.



4.  Security Considerations

   The SMPTE URN Namespace ID shares the security considerations
   outlined in [RFC3406], but has no other known security

5.  Namespace Considerations and Community Considerations

   SMPTE is an internationally-recognized standards-developing
   organization.  As part of this effort, SMPTE also registers items
   such as Universal Labels through the SMPTE Registration Authority.
   The SMPTE namespace provides a uniform, unique, and effective way to
   communicate resource names for these items, which can be used by the
   motion imaging industry community.  This namespace is also intended
   to be a useful mechanism to provide both human and automated access
   to these resources through online systems.

   The individual URNs in the namespace shall be assigned through the
   process of development of documents by SMPTE, through definition by
   SMPTE standards, or through the registration of Universal Labels or
   other items by the SMPTE Registration Authority.

   RFC 3406 states that a URN registration RFC must include a 'Namespace
   Considerations' section, which outlines the perceived need for a new
   namespace.  There are four areas where existing URN namespaces fall
   short of the requirements for a SMPTE URN namespace.

      URN assignment procedures: URNs for resources defined by SMPTE
      standards must be assigned exclusively by SMPTE or its delegates
      to ensure the integrity of the standards process.  No other
      existing URN namespace has URNs assigned and managed by SMPTE.

      URN resolution: URNs assigned by SMPTE standards must be resolved
      by SMPTE mechanisms such as the SMPTE Registration Authority to

      ensure the integrity of the standards process.  This resolution
      may require the reference of databases only maintained by SMPTE.

      Types of resources to be identified: Many resources defined by
      SMPTE standards (such as Universal Labels) have no adequate
      existing URN representation.

      Types of services to be supported: SMPTE expects to establish Web
      services for the automated resolution of resources defined by
      SMPTE standards utilizing the SMPTE URN namespace.

6.  IANA Considerations

   This document defines a URN NID registration that has been entered
   into the IANA registry of URN NIDs.  IANA has registered the NID

7.  SMPTE Registration Authority (Informative)

   The URL of the SMPTE Registration Authority is

8.  References

8.1.  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.

   [SMPTE2029] Society of Motion Picture and Television Engineers,
               "Uniform Resource Names for SMPTE Resources", SMPTE
               2029-2007, <http://www.smpte.org>.

8.2.  Informative References

   [ISO8824-1] International Organization for Standardization,
               "Information Processing - Open System Interconnection -
               Specification of Abstract Syntax Notation One (ASN.1)",
               ISO Standard 8824-1:1995, 1995.

   [RFC3061]   Mealling, M., "A URN Namespace of Object Identifiers",
               RFC 3061, February 2001.

   [RFC4234]   Crocker, D., Ed., and P. Overell, "Augmented BNF for
               Syntax Specifications: ABNF", RFC 4234, October 2005.

   [RP210]     Society of Motion Picture and Television Engineers,
               "Metadata Dictionary Registry of Metadata Element
               Descriptions", SMPTE RP210, <http://www.smpte.org>.

   [RP224]     Society of Motion Picture and Television Engineers,
               "Registry of SMPTE Universal Labels", SMPTE RP224,

   [SMPTE298M] Society of Motion Picture and Television Engineers,
               "Universal Labels for Unique Identification of Digital
               Data", ANSI / SMPTE 298M-1997, <http://www.smpte.org>.

   [SMPTE336M] Society of Motion Picture and Television Engineers, "Data
               Encoding Protocol using Key-Length-Value", SMPTE 336M-
               2001, <http://www.smpte.org>.

Author's Address

   Thomas G. Edwards
   10201 West Pico Boulevard
   Los Angeles, CA  90035

   Phone: +1 310 369 7093
   Email: thomas.edwards@fox.com
   URI:   http://www.fox.com

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