Internet DRAFT - draft-rozenfeld-urn-issn

draft-rozenfeld-urn-issn





Network Working Group                                  Slawek Rozenfeld
Internet-Draft : draft-rozenfeld-urn-issn-00.txt
28 August 2000                                ISSN International Centre
Category: Informational
Expires: February 28, 2001



      Using The ISSN (International Serial Standard Number) as
      URN (Uniform Resource Names) within an ISSN-URN Namespace


Status of this Memo

This document is an Internet-Draft and is in full conformance with all
provisions of Section 10 of RFC2026.

Internet-Drafts are working documents of the Internet Engineering Task
Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.

Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsolete by other documents at any
time. It is inappropriate to use Internet-Drafts as reference material
or to cite them other than as "work in progress."

The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/lid-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.

This Internet-Draft will expire on February 28, 2001.


Abstract

This draft document presents how the ISSN - International Standard
Serial Number - which is a persistent number for unique 
identification of serials widely recognised and used in the
bibliographic world, can be supported within the URN framework as a
specific URN namespace identifier.
An ISSN URN resolution system using the ISSN identifier as Uniform
resource Name within an ISN URN Namespace has been developed by the
ISSN International Centre (ISSN-IC) and is operating as a demonstrator
to evaluate all requirements to deploy it in an operational
environment.
This proceeds from concepts and proposals developed in several IETF
RFCs emphasising the way to implement and to use "recognised" existing
numbering system within the URN framework.
(RFC 2248 [Lynch], RFC 2141 [Moats], RFC2611[Daigle, Iannella]



S. ROZENFELD             Informational                        [Page 01]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

Table of Contents

  1. Introduction
  2. The ISSN system
    2.1 The ISSN
    2.2 The ISSN bibliographic record
    2.2 The ISSN Network
    2.3 The ISSN Register
  3. The ISSN and URN
    3.1 compatibility
    3.2 identification and access
  4  Resolution
    4.1 Overview of the ISSN URN Resolution system
    4.2 Global Resolution
  5. Registration of an ISSN URN Namespace
  6. References
  7. Contact information and useful links
  8. Full copyright statement
  9. Date of expiration.

1. Introduction

The ISSN International Centre has undertaken in 1999-2000 an URN
implementation taking advantage of the functional compatibility
between the ISSN and the URN.
The present implementation at the ISSN-IC Centre based on IETF RFCs on
URN includes a centralised resolution system which allows direct access
to electronic resources by using the ISSN identifiers as Uniform
Resource Names within an ISSN URN Namespace.
It demonstrates that the URN can integrate existing identifiers from
well established identification schemes used by the bibliographic
community.
Nevertheless, to deploy this demonstrator into a wider operational
system a responsible body or infrastructure is needed to assign
namespaces and manage an RDS/NAPTR global resolution framework.
It is intended here that serials refer to all forms of serials
published in printed form as well as in form of electronic resources.
Since this document contains a Registration form for an ISSN URN
Namespace, this form also includes some paragraphs already present in
other parts of this draft.
All figures and  descriptions are dated  13 July 2000

2. The ISSN system

The ISSN system results from a joint UNESCO and ICSU-AB working group
on bibliographic descriptions set up in 1967 in order to establish a
world registry of serial titles currently issued, stored  or archived.

Today, the ISSN system which is defined by an International standard
(ISO 3297), relies on two main data elements:
The International Standard Serial Number which is a unique identifier
for a specific serial publication.




S. ROZENFELD             Informational                        [Page 02]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

The key-title, which is a unique name assigned to a serial, and is
inseparably linked with its ISSN.
And on a well established framework : the ISSN International network.

2.1 The ISSN code

The ISSN - International Standard Serials Number is defined in the ISO
standard 3297:1998 as a code for the unique identification of serials.

This standard states that :
Each ISSN is a unique identifier for a specific serial publication.
ISSN are applicable to the entire population of serials, whether past,
present or to be published in the foreseeable future, whatever the
medium of publication.
Serials include  periodicals, newspapers, annuals (such as reports,
yearbooks, directories, etc.), and the journals, series, memoirs,
proceedings, transactions, etc. of societies.
Today, ISSN are assigned to data bases and electronic serial
resources. Further broadening of the scope to continuing resources
is under discussion.

2.2 Construction of ISSN

The ISO 3297 standard states that:
An ISSN consists of eight digits in arabic numerals 0 to 9, except
the last digit which is a check digit and can be sometimes an X.
The ISSN has no internal meaningful elements to identify language,
country, publisher  [or medium.]
The check digit is always located in the extreme right position and is
calculated on a modulus 11 basis with weights 8 to 2 , using X in lieu
of 10  where 10 would occur as a check digit.
Each ISSN isinseparably linked a "the key title". The Key title is a
form of the title which is constructed  in order to avoid duplicates so
that each key title is unique in the ISSN Data base also named the
ISSN Register. ISSN and key titles are equivalent,they both identify
without ambiguity a same serial.
When printed or displayed the ISSN is preceded by the ISSN prefix and a
space , and shall appear as two groups of four digits separated by a
hyphen

examples  ISSN 0000-0019   ISSN 1560-1560

ISSN are constructed and distributed by the ISSN International Centre 
to National Centres for assignment.


2.2 The ISSN Bibliographic record

It contains in addition to the ISSN and key-title some thirty
bibliographic data elements enabling the unambiguous and secure
identification of a serial.





S. ROZENFELD             Informational                        [Page 03]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

One characteristic of an ISSN bibliographic record is that it contains
other ISSN in linking fields in order to establish relationships
 between the given serial and a set of other related serials already 
identified.

To recognise and to allow access to serial resources in digital form,
the ISSN format has included additional data elements :

- A medium code which indicates the medium of the given serial
- A linking field to express relations between the different forms
of "equivalent" serials on different media (from printed version
to online as well as from online to printed)
- The location of an electronic resource : the URLs of a given
resource.


2.3 The ISSN network

It is the operational structure, main functions of which are :
- collecting the material which needs to be identified
- assigning the ISSN and the key title to a serial for unambiguous
identification
- creating and editing  bibliographic records in ISSN format
- making available the bibliographic records

It consists of :

- National Centres - 69 centres- responsible for the identification of
serials published in their respective countries.
Records created by National Centres are transmitted to the ISSN-IC for
validation and update of the ISSN Register.

- The International Centre which co-ordinates the network and acts as a
National Centre for serials published by International institutions and
by countries with no National Centre.
It collects and checks all bibliographic records to update in a
consistent way the ISSN Register.
It maintains the ISSN Register and makes it available.

2.4 The ISSN Register

It is a  data base controlled and maintained by the ISSN-IC.
It consists in 970 000 bibliographic records stored in ISSN-MARC format
(a subset of USMARC format ) which are available on different media
(CD-ROM, DAT, and on the Internet).


3. THE ISSN AND URN

3.1 ISSN compliance with URN requirements

The different specifications and requirements on URNs have been studied
from the following documents



. ROZENFELD             Informational                         [Page 04]

INTERNET-DRAFT       draft-ietf-urn-issn-00.txt             August 2000

URN Syntax
(RFC 2141, May 1997 - R.Moats)

Using Existing Bibliographic Identifiers as Uniform Resource Names
(RFC 2288 February 1998 - C. Lynch, R; Daniel)

Functional Requirements for Uniform Resource Names
(RFC 1737, December 1994 - K. Sollins, L. Masinter)

URN Namespace Definition Mechanisms
(RFC2611, June 1999 - Leslie L.Daigle, Renato Iannella)

A URN Namespace for IETF Documents
(RFC2648, August 1999 - R. Moats)

Requirements for URNs' functional capabilities (from RFC 1737)

Global scope: A URN is a name with global scope which does not imply a
location. It has the same meaning everywhere.
- Applicable for ISSN. Accordingly to ISO standard 3297 there is no
limitations for serial resource identification.

Global uniqueness: The same URN will never be assigned to two different
resources.
- Applicable for ISSN. By definition an ISSN is assigned to one and
only one serial resource. Once assigned, an ISSN is never re-assigned.

Persistence: The lifetime of a URN is permanent.
- Applicable for ISSN. All ISSN are registered in the ISSN Register
data base which covers current serial resources as well as ceased.

Scalability: URNs can be assigned to any resource that might
conceivably be available on the network, for hundreds of years.
- Applicable for ISSN. More than 98500000 ISSN have yet been assigned.

Legacy support: The scheme must permit the support of existing legacy
naming systems
- Applicable for ISSN. By definition the ISSN system is a legacy
identification system for serial resources.

Independence: It is solely the responsibility of a name issuing
authority to determine the conditions under which it will issue a name.
- Applicable for ISSN. By definition of the ISSN system.

Resolution: For URNs that have corresponding URLs, there must be some
feasible mechanism to translate a URN to a URL.
- Applicable for ISSN. The ISSN-IC has developed an ISSN URN resolver
which translates one given ISSN into one or several URLs.

In addition to these basic requirements on the functional elements
of the URNs, there are other requirements for how they are encoded
in a string:



S. ROZENFELD             Informational                        [Page 05]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000


Single encoding, Simple comparison, Simple human transcribability,
Transport friendliness, Machine consumption, Text recognition.
- Applicable to ISSN. As defined in the ISO standard the  ISSN is a
very simple and short character string which fully responds to those
requirements.

Considering the aim of the ISSN, its framework and new developments for
electronic serial resources identification, we can state that the
ISSN fulfils all expressed URN requirements


Syntax requirements

Considering syntax requirements (RFC2141) for an URN namespace and the
URN syntax, an ISSN based URN namespace is compliant with such
requirements since it does not use any reserved characters.

In RFC2288 ( 4.2 Encoding Considerations and Lexical  Equivalence) it
is stated that:

 There is no problem representing ISSN in the namespace- specific
string of URNs since all characters valid in the ISSN are valid in the
namespace-specific URN string, and %-encoding is never  required.

Example: urn:ISSN:1046-8188

Supplementary comparison rules are also appropriate for the ISSN
namespace, hyphens should be dropped prior to comparison and
occurrences of 'x' normalised to uppercase.


3.2 Identification and access

The role of an URN is also to provide safe access to the
characteristics of a resource and to the resource itself.
One may view an ISSN bibliographic record as a metadata since it
contains different data information on the resource which is to be
identified, described, located and/or accessed

The ISSN is widely used as an identification number for serial
resources. Since the ISSN Network provides the URLs corresponding to
the identified resources the ISSN is now also a tool for the location
and access to resources on the Internet.
This is achieved by an ISSN URN resolution system.


4. RESOLUTION

The different specifications and requirements on URN  resolution have
been studied from the following documents





S. ROZENFELD             Informational                        [Page 06]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000


URI Resolution Services Necessary for URN Resolution
(RFC 2483, January 1999 - M.. Mealling)

Resolution of Uniform Resource Identifiers using the Domain Name System
(RFC2168 June 1997 - R. Daniel, M. Mealling )

Architectural Principles of Uniform Resource Name Resolution
(RFC 2276, January 1998 - K.Sollins )


4.1 . Overview of the ISSN URN Resolution system

Using ISSN as Uniform Resource Name implies that some mapping mechanism
is provided to ensure a reliable access to available resources when 
using Internet tools like a standard Web browser.

>From the technical point of view this has led to develop within our
system the different pieces of software and services required to fulfil
such aim.
The resolution software be able to translate a given ISSN-URN into
electronic locations :
- location of the bibliographic description or metatada
- location of the periodical itself (if it is in electronic form ).

These electronic locations are expressed in form of URLs for which
persistence is not ensured. As a consequence the URLs which are stored
for resolution have to be checked and updated to ensure relevant
mapping with the corresponding URNs.

The URLs which are stored in the database must be checked regularly for
accuracy and if changes occur they have to be reported in the ISSN-URN
resolver database.
The browser has to include the URN facility which allows to express the
location of a given resource in form of an ISSN, this means that if the
standard browsers do not include the URN option a "plug-in" is to be
developed.

Thus, four types of developments have been considered :

Design and implementation of a resolver :
-In a first step a global centralised resolution system has been
developed and implemented on one resolution server located at the
ISSN International Centre.
It ensures effective mapping between a given ISSN and one or several
URL(s) which implies that "multiple resolution" is performed.
Design and implementation of an ISSN-URL mapping file

-Today, the principal method to map ISSN with URLs is to extract
them from ISSN registered records and to store them in a separate file
structured specially for the resolution process. Besides, other ways to
get URLs for bibliographic resources identified by ISSN are tested.
Management data as well as attributes are linked to URLs in order to
recognise objects handled by the resolver.



S. ROZENFELD             Informational                        [Page 07]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

Design and implementation of an URL checker :
-In order to control the persistence and the accessibility to ISSN-URN
a robot called the "URL Watcher" has been written to control the status
of all URLs stored in the ISSN-URL mapping file. Broken or redirected
URLs are detected and stored to permit efficient resolution.

Design and implementation of a browser plug-in :
-The existing browsers do not include today the URN "protocol"
functionality. One expect to have it implemented in a near future.
A plug-in for Netscape communicator and MS-Explorer has been
developed and is available.

This enables to enter directly the ISSN preceded by the string
"urn:ISSN:" in the browsers address box instead of typing the URL and
as result to get displayed the bibliographic record or/and the online
resource. Clicking on an ISSN on an HTML page gives the same result.
    example: urn:ISSN:1560-1560


4.2 Global resolution

Since the ISSN system is not addressing a local environment (like a
given Library) and is expected to be linked to other URNs (or other
identification services) for identification of serial related resources
having other levels of granularity, we have to consider an evolution
of the present resolution implementation to a global resolution system.

Resolution and especially global resolution is considered as a major
issue for becoming an ISSN URN Namespace.
This is expressed in the following statement (from RFC 2611 "the URN
Namespace Definition mechanisms "):

Process for identifier resolution:
  If a namespace is intended to be accessible for global resolution,
  it must be registered in an RDS (Resolution Discovery System,
  see [RFC2276]) such as NAPTR. Resolution then proceeds according to
  standard URI resolution processes, and the mechanisms of the RDS.

Our present views and evaluations to be integrated in such RDS System
for global resolution for an ISSN URN Namespace are mainly based on
concepts and proposals from the following RFCs :
RFC 2276 for RDS architecture for global resolution,
RFC 2168 for the NAPTR DNS extension,

>From a technical point of view our present resolution system is
flexible enough to take place in a RDS/NAPTR resolution framework.










S. ROZENFELD             Informational                        [Page 08]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

5. Namespace registration


Namespace ID:

       ISSN

Registration Information:

      Version 1
      Date: 2000-08-28

Declared registrant of the namespace:

      Name:         S. ROZENFELD (Mr.)

      E-mail:       rozenfeld@issn.org

      Affiliation:  ISSN International Centre

      Address: 20, rue Bachaumont
                      75002 PARIS
                           FRANCE


Declaration of syntactic structure:

In accordance with the ISO standard 3297 - Information and
documentation International Standard Serial Number(ISSN)-(1998)

The ISSN consists of eight digits in Arabic numerals 0 to 9, except the
last digit which is a check digit and can sometimes  be an X.
The ISSN has no internal meaningful elements to identify language,
country, publisher.
The check digit is always located in the extreme right position and is
calculated on a modulus 11 basis with weights 8 to 2 , using X in lieu
of 10  where 10 would occur as a check digit.
Each ISSN is inseparably linked to the serials title "the key title"
which is a constructed form of the title in order to avoid duplicates
so that each key title is unique within the ISSN Data base.
ISSN and key titles are equivalent, they both identify without
ambiguity a same serial.
When printed or displayed the ISSN is preceded by the ISSN prefix and a
space , and shall appear as two groups of four digits separated by a
hyphen

 Therefore the ISSN structure is as follows:

	NNNN-NNNC

         where N is a Digit character [0..9]
               C is either a Digit character or letter "X" [0..9,X]
               C is the check character



S. ROZENFELD             Informational                        [Page 09]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

 An ISSN URN Namespace structure is conformant to URN syntax
 requirements (RFC 2141).


          examples urn:ISSN:0259-000X
                   urn:ISSN:1560-1560

Relevant ancillary documentation:


 ISO 3279 Information and documentation - International Standard
 Serial Number (ISSN)

 The ISSN : an identifier for serials in digital form.
 Compatibility with the URN framework.
 (ISSN International Centre -  January 1999)

 The ISSN-URN project.
 (ISSN International Centre -  October 1999)


Identifier uniqueness considerations:

 Uniqueness is guaranteed by ISSN definition.

 As defined in the ISO 3279 each ISSN is a "unique" identifier for a
 specific serial publication.

 A different ISSN is assigned to each publication issued on different
 media.

 An ISSN is never re-assigned.


Identifier persistence considerations:

 Persistence of ISSN is guaranteed by the maintenance and update
 of the ISSN Register by the ISSN Centres.
 Even records for "ceased" publications still remain in the
 ISSN database, and links between serials belonging to a
 same "family" are expressed with related ISSN within the records.
 This linking  mechanism extends the current Identifier persistence
 concept.


Process of identifier assignment:

 The ISSN network consisting in 68 National Centres and the
International Centre :







S. ROZENFELD             Informational                        [Page 10]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

   - collects the material to be identified
   - checks for identification all types of serials including
     electronic serial resources.
   - assigns an ISSN to each different periodical.
   - establish the bibliographic record.
   - makes available the data.

 The data consisting in bibliographic records is centralised at the
ISSN International Centre for global uniqueness checking.
 A given ISSN  refers to one and only one form of the title,
 he key-title which is a key element of the bibliographic record as
well as the ISSN.

 Today, the ISSN database contains more than 950 000 bibliographic
 records and a special attention is given to electronic publication
 resources and related metadata, and the way to access them.


Process for identifier resolution:

 As a first step the ISSN International Centre has developed a
 centralised ISSN-URN resolver with multiple resolution capabilities
 which runs as a demonstrator.

 In a second step we expect the ISSN Namespace to be accessible for
 global resolution and to provide a set of resolution services
 compliant  with the RDS/NAPTR proposals.

Rules for Lexical Equivalence:

 The check digit if 'X' is case-sensitive.
 Thus, if "x" is found it must be translated in upper case.

 The hyphen between the 4th and the 5th digit can be omitted

Conformance with URN Syntax:

 There are no characters reserved.

Security Considerations

 Because this namespace defines no additional reserved characters it
 does not add any security consideration.

Validation mechanism:

 None specified today.

Scope:

 Global.





S. ROZENFELD             Informational                        [Page 11]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

6. References

 ISO 3279 Information and documentation - International Standard Serial
 Number (ISSN)

 The ISDS Manual - ISSN International Centre( Paris, 1983)
 (under revision)

 Ryan Moats, "URN Syntax", RFC 2141, May 1997.

 Karen R Sollins & Larry Masinter, "Functional Requirements for Uniform
 Resource Names", RFC1737, December 1994

 C. Lynch, C. Preston & R. Daniel, "Using Existing Bibliographic
 Identifiers as Uniform Resource Names", RFC 2288, February 1998.

 Ron Daniel & Michael Mealling, "Resolution of Uniform Resource
 Identifiers using the Domain Name System", RFC 2168, June 1997.

 K. Sollins, "Architectural Principles of Uniform Resource Name
 Resolution", RFC 2276, January 1998.


 7. Contact Information and useful links

    Slawek Rozenfeld (Mr.)
    Head, Computer Section
    ISSN International Centre
      20, rue Bachaumont
            750002 PARIS
                  FRANCE

    E-Mail: rozenfeld@issn.org
            issnic@issn.org

    ISSN Web site  http://www.issn.org
    ISSN-URN links http://www.issn.org/urn/



















S. ROZENFELD             Informational                        [Page 12]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000

 8.  Full Copyright Statement
   Copyright (C) The Internet Society (2000).  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
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph
   are 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 organisations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   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 assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

9. Date of expiration

 This Internet-Draft will expire on February 28, 2001.


























S. ROZENFELD             Informational                        [Page 13]

INTERNET-DRAFT        draft-ietf-urn-issn-00.txt            August 2000