Network Working Group J. Smith
Request for Comments: 3614 IBM T. J. Watson Research Center
Category: Informational September 2003
A Uniform Resource Name (URN) Namespace for the
Motion Picture Experts Group (MPEG)
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.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This document describes a Uniform Resource Name (URN) namespace for
the Motion Picture Experts Group (MPEG) for naming persistent
resources as part of the MPEG standards. Example resources include
technical documents and specifications, eXtensible Markup Language
(XML) Schemas, classification schemes, XML Document Type Definitions
(DTDs), namespaces, style sheets, media assets, and other types of
resources produced or managed by MPEG.
1. Introduction
MPEG is a working group of the International Organization for
Standardization (ISO) and International Engineering Consortium (IEC)
in charge of the development of standards for coded representation of
digital audio and video. MPEG has produced MPEG-1, the standard on
which such products as Video CD and MP3 are based, MPEG-2, the
standard on which such products as Digital Television set top boxes
and DVD are based, MPEG-4, the standard for multimedia for the fixed
and mobile web, and MPEG-7, "Multimedia Content Description
Interface", the standard for description and search of audio and
visual content. Work on MPEG-21, "Multimedia Framework" is currently
underway.
MPEG would like to assign unique, permanent, location-independent
names based on URNs for some resources it produces or manages.
This namespace specification is for a formal namespace.
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RFC 3614 URN Namespace for MPEG September 2003
2. Specification Template
Namespace ID:
"mpeg"
Registration Information:
Version: 1
Date: 2001-11-20
Declared registrant of the namespace:
Name: John R. Smith
Title: Chair, MPEG MDS Subgroup
Affiliation: IBM T. J. Watson Research Center
Address: 30 Saw Mill River Road
Hawthorne, NY 10532 USA
Phone: +1 (914) 784-7320
Email: jrsmith@watson.ibm.com
Declaration of structure:
URNs assigned by MPEG will have the following hierarchical
structure based on the organizational structure of the MPEG
standards:
urn:mpeg:{standard name}:{assigned US-ASCII string}
where "{standard name}" is a US-ASCII string that conforms to URN
Syntax requirements ([RFC2141]) and corresponds to the name of an
MPEG standard (such as "mpeg1", "mpeg2", "mpeg4", "mpeg7",
"mpeg21", and
"{assigned US-ASCII string}" is a US-ASCII string that conforms to
URN Syntax requirements ([RFC2141]).
The individual URNs shall be assigned by MPEG through the process
of development of MPEG standards.
Relevant ancillary documentation:
None
Identifier uniqueness considerations:
MPEG shall establish unique identifiers as appropriate.
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Uniqueness is guaranteed as long as the assigned string is never
reassigned for a given standard name and that the standard name is
never reassigned.
Identifier persistence considerations:
MPEG is committed to maintaining the accessibility and persistence
of all resources that are officially assigned URNs by the
organization.
Persistence of identifiers is dependent upon suitable delegation
of resolution at the level of "standard name"(s), and persistence
of standard name assignment.
Process of identifier assignment:
Assignment is limited to the owner and those authorities that are
specifically designated by the owner. MPEG may designate portions
of its namespace for assignment by other parties.
Process of identifier resolution:
The owner will develop and maintain "URN catalogs" that map all
assigned URNs to Uniform Resource Locators (URLs) specifically to
enable Web-based resolution of named resources. In the future an
interactive online resolution system may be developed to automate
this process.
The owner will authorize additional resolution services as
appropriate.
Rules for Lexical Equivalence:
The "standard name" is case-insensitive. Thus, the portion of the
URN:
urn:mpeg:{standard name}:
is case-insensitive for matches. The remainder of the identifier
must be considered case-sensitive.
Conformance with URN Syntax:
No special considerations.
Validation mechanism:
None specified. The owner will develop and maintain URN catalogs.
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RFC 3614 URN Namespace for MPEG September 2003
The presence of a URN in a catalog indicates that it is valid.
Scope:
Global
3. Examples
The following examples are not guaranteed to be real. They are
presented for pedagogical reasons only.
urn:mpeg:mpeg7:schema:2001
urn:mpeg:mpeg7:cs:VideoDomainCS:2001
urn:mpeg:mpeg7:cs:GenreCS:2001
urn:mpeg:mpeg7:cs:ContentCS:2001
4. Namespace Considerations
URN assignment procedures:
The individual URNs shall be assigned through the process of
development of MPEG standards by the Moving Picture Experts Group
(MPEG), which is a working group of ISO/IEC.
URN resolution/delegation:
The resolution and delegation shall be determined through the
process of development of MPEG standards by the Moving Picture
Experts Group (MPEG). MPEG has developed requests for
registration authority for MPEG-7 classification schemes and
MPEG-21 identification systems. These registration authorities
shall be responsible for corresponding parts of MPEG namespace.
Type of resources to be identified:
Types of resources to be identified include XML schema definition
files, classification schemes, identification systems.
Type of services to be supported:
Types of services supported include controlled term lookup in
classification schemes, resolution of ids in identification
systems.
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5. Community Considerations
Open assignment and use of identifiers within the namespace:
With on-going development of MPEG standards, MPEG shall establish
requirements for assignment and use of identifiers within MPEG
namespace. MPEG has already established requirements for
assignment and use of MPEG-7 classification schemes under MPEG
namespace. A registration authority shall have the responsibility
for processing third party requests for registering classification
schemes.
Open operation of resolution servers for the namespace (server):
With on-going development of MPEG standards, MPEG shall establish
requirements and seek candidates for operating resolution servers
as appropriate.
Creation of software that can meaningfully resolve and access
services for the namespace (client):
With on-going development of MPEG standards, MPEG shall develop
reference software implementations of its standards.
6. Security Considerations
There are no additional security considerations other than those
normally associated with the use and resolution of URNs in general.
7. IANA Considerations
The IANA has registered formal URN namespace 12, to MPEG within the
IANA registry of URN NIDs.
8. Normative References
[RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
9. Author's Address
John R. Smith
IBM T. J. Watson Research Center
30 Saw Mill River Road
Hawthorne, NY 10532 USA
Phone: 1 (914) 784-7320
EMail: jrsmith@watson.ibm.com
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RFC 3614 URN Namespace for MPEG September 2003
10. Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
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included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
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followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees.
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Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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