draft-ietf-urn-biblio-00.txt   draft-ietf-urn-biblio-01.txt 
Internet Draft Clifford Lynch Internet Draft Clifford Lynch
draft-ietf-urn-biblio-00.txt University of California September 8. 1997 Coalition for Networked Information
22 March 1997 Cecilia Preston draft-ietf-urn-biblio-01.txt Cecilia Preston
Expires in six months Preston & Lynch Preston & Lynch
Ron Daniel Jr. Ron Daniel Jr.
Los Alamos National Laboratory Los Alamos National Laboratory
Using Existing Bibliographic Identifiers Using Existing Bibliographic Identifiers
as as
Uniform Resource Names Uniform Resource Names
Status of this Document Status of this Document
This document is an Internet-Draft. Internet-Drafts are This document is an Internet-Draft. Internet-Drafts are
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(IETF), its areas, and its working groups. Note that other (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet- groups may also distribute working documents as Internet-
Drafts. Drafts.
Internet-Drafts are draft documents valid for a maximum of Internet-Drafts are draft documents valid for a maximum of
six months and may be updated, replaced or made obsolete by six months and may be updated, replaced or made obsolete by
other documents at any time. It is inappropriate to use other documents at any time. It is inappropriate to use
Internet-Drafts as reference material or to cite them other Internet-Drafts as reference material or to cite them other
than as works in progress. than as works in progress.
Distribution of this document is unlimited. Please send Distribution of this document is unlimited.
comments to clifford.lynch@ucop.edu and cecilia@well.com.
This document does not specify a standard; it is purely This document does not specify a standard; it is purely
informational. informational.
0. Abstract 0. Abstract
A system for Uniform Resource Names (URNs) must be capable A system for Uniform Resource Names (URNs) must be capable
of supporting identifiers from existing widely-used naming of supporting identifiers from existing widely-used naming
systems. This document discusses how three major systems. This document discusses how three major
bibliographic identifiers (the ISBN, ISSN and SICI) can be bibliographic identifiers (the ISBN, ISSN and SICI) can be
supported within the URN framework and the currently supported within the URN framework and the currently
proposed syntax for URNs. proposed syntax for URNs.
1. Introduction 1. Introduction
The ongoing work of several IETF working groups, most The ongoing work of several IETF working groups, most
recently in the Uniform Resource Names working group, has recently in the Uniform Resource Names working group, has
culminated the development of a syntax for Uniform Resource culminated the development of a syntax for Uniform Resource
Names (URNs). The functional requirements and overall Names (URNs). The functional requirements and overall
framework for Uniform Resource Names are specified in RFC framework for Uniform Resource Names are specified in RFC
1737 [Sollins & Masinter] and the current proposal for the 1737 [Sollins & Masinter] and the specification for the
URN syntax is draft-ietf-urn-syntax-04.txt [Moats]. URN syntax is RFC 2141 [Moats].
As part of the validation process for the development of As part of the validation process for the development of
URNs the IETF working group has agreed that it is important URNs the IETF working group has agreed that it is important
to demonstrate that the current URN syntax proposal can to demonstrate that the current URN syntax proposal can
accommodate existing identifiers from well managed accommodate existing identifiers from well established
namespaces. One such well-established infrastructure for namespaces. One such infrastructure for assigning and
assigning and managing names comes from the bibliographic managing names comes from the bibliographic community.
community. Bibliographic identifiers function as names for Bibliographic identifiers function as names for objects that
objects that exist both in print and, increasingly, in exist both in print and, increasingly, in electronic formats.
electronic formats. This Internet draft demonstrates the This Internet draft demonstrates the feasibility of
feasibility of supporting three representative bibliographic supporting three representative bibliographic identifiers
identifiers within the currently proposed URN framework and within the currently proposed URN framework and syntax.
syntax.
Note that this document does not purport to define the Note that this document does not purport to define the
"official" standard way of doing so; it merely demonstrates "official" standard way ofmoving these bibliographic
feasibility. It has not been developed in consultation with identifiers into URNs; it merely demonstrates feasibility.
the standards bodies and maintenance agencies that oversee It has not been developed in consultation with these
the existing bibliographic identifiers. Any actual Internet standards bodies and maintenance agencies that oversee the
existing bibliographic identifiers. Any actual Internet
standard for encoding these bibliographic identifiers as standard for encoding these bibliographic identifiers as
URNs will need to be developed in consultation with the URNs will need to be developed in consultation with the
responsible standards bodies and maintenance agencies. responsible standards bodies and maintenance agencies.
In addition, there are several open questions with regard to In addition, there are several open questions with regard to
the management and registry of Namespace Identifiers (NIDs) the management and registry of Namespace Identifiers (NIDs)
for URNs. For purposes of illustration, we have used the for URNs. For purposes of illustration, we have used the
three NIDs "ISBN", "ISSN" and "SICI" for the three three NIDs "ISBN", "ISSN" and "SICI" for the three
corresponding bibliographic identifiers discussed in this corresponding bibliographic identifiers discussed in this
document. While we believe this to be the most appropriate document. While we believe this to be the most appropriate
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URNs will need to be developed in consultation with the URNs will need to be developed in consultation with the
responsible standards bodies and maintenance agencies. responsible standards bodies and maintenance agencies.
In addition, there are several open questions with regard to In addition, there are several open questions with regard to
the management and registry of Namespace Identifiers (NIDs) the management and registry of Namespace Identifiers (NIDs)
for URNs. For purposes of illustration, we have used the for URNs. For purposes of illustration, we have used the
three NIDs "ISBN", "ISSN" and "SICI" for the three three NIDs "ISBN", "ISSN" and "SICI" for the three
corresponding bibliographic identifiers discussed in this corresponding bibliographic identifiers discussed in this
document. While we believe this to be the most appropriate document. While we believe this to be the most appropriate
choice, it is not the only one. The NIDs could be based on choice, it is not the only one. The NIDs could be based on
the standards body and standard number (e.g. "US-ANSI-NISO- the standards body and standard number (e.g. "US-ANSI-NISO-
Z39.56-1997" rather than "SICI"). Alternatively, one could Z39.56-1997" rather than "SICI"). Alternatively, one could
lump all bibliographic identifiers into a single lump all bibliographic identifiers into a single
"BIBLIOGRAPHIC" name space, and structure the namespace- "BIBLIOGRAPHIC" name space, and structure the namespace-
specific string to specify which identifier is being used. specific string to specify which identifier is being used.
We do not believe that these are advantageous approaches, Any final resolution of this must wait for the outcome of
but must wait for the outcome of namespace management namespace management discussions in the working group and
discussions in the working group. the broader IETF community.
For the purposes of this document, we have selected three For the purposes of this document, we have selected three
major bibliographic identifiers (national and international) major bibliographic identifiers (national and international)
to fit within the URN framework. These are the to fit within the URN framework. These are the International
International Standard Book Number (ISBN) [ISO1], the Standard Book Number (ISBN) [ISO1], the International
International Standard Serials Number (ISSN) [NISO1,ISO2, Standard Serials Number (ISSN) [NISO1,ISO2, ISO3], and the
ISO3], and the Serial Item and Contribution Identifier Serial Item and Contribution Identifier (SICI) [NISO2]. An
(SICI) [NISO2]. ISBNs are used to identify monographs ISBN is used to identify a monograph (book). An ISSN is used
(books). ISSNs are used to identify serial publications to identify serial publications (journals, newspapers) as a
(journals, newspapers) as a whole. SICIs augment the ISSN whole. A SICI augments the ISSN in order to identify
in order to identify individual issues of serial individual issues of serial publications, or components
publications, or components within those issues (such as an within those issues (such as an individual article, or the
individual article, or the table of contents of a given table of contents of a given issue). The ISBN and ISSN are
issue). The ISBN and ISSN are defined in the United States defined in the United States by standards issued by the
by standards issued by the National Information Standards National Information Standards Organization (NISO) and also
Organization (NISO) and also by parallel international by parallel international standards issued under the auspices
standards issued under the auspices of the International of the International Organization for Standardization (ISO).
Organization for Standardization (ISO). NISO is the ANSI- NISO is the ANSI-accredited standards body serving libraries,
accredited standards body serving libraries, publishers and publishers and information services. The SICI code is
information services. The SICI code is defined by a NISO defined by a NISO document in the United States and does not
document in the United States and does not have a parallel have a parallel international standards document at present.
international standards document at present.
Many other bibliographic identifiers are in common use (for Many other bibliographic identifiers are in common use (for
example, the CODEN, numbers assigned by major bibliographic example, CODEN, numbers assigned by major bibliographic
utilities such as OCLC and RLG, national library numbers utilities such as OCLC and RLG, national library numbers such
such as the Library of Congress Control Number) or are under as the Library of Congress Control Number) or are under
development. While we do not discuss them in this document, development. While we do not discuss them in this document,
many of these will also need to be supported within the URN many of these will also need to be supported within the URN
framework as it moves to large scale implementation. The framework as it moves to large scale implementation. The
issues involved in supporting those additional identifiers issues involved in supporting those additional identifiers
are anticipated to be broadly similar to those involved in are anticipated to be broadly similar to those involved in
supporting ISBNs, ISSNs, and SICIs. supporting ISBNs, ISSNs, and SICIs.
2. Identification vs. Resolution 2. Identification vs. Resolution
It is important to distinguish between the resource It is important to distinguish between the resource
identified by a URN and the resources that can reasonably be identified by a URN and the resources a URN resolver that can
provided when attempting to resolve an identifier. For reasonably return when attempting to resolve an identifier.
For example, the ISSN 0040-781X identifies the popular
example, the ISSN 0040-781X identifies the popular magazine "Time" -- all of it, every issue for from the start
"Time". All of it, every issue for from the start of of publication to present. Resolving such an identifier
publication to present. Resolving such an identifier should should not result in the equivalent of hundreds of thousands
not result in the equivalent of hundreds of thousands of of pages of text and photos being dumped to the user's
pages of text and photos being dumped to the user's machine. machine. It is more reasonable for ISSNs to resolve to a
It is more reasonable for ISSNs to resolve to a navigational navigational system, such as an HTML-based search form, so
system, such as an HTML-based search form, so the user may the user may select issues or articles of interest. ISBNs
select issues or articles of interest. ISBNs and SICIs, on and SICIs, on the other hand, do identify finite, manageably-
the other hand, do identify finite, manageably-sized sized objects, but these objects may still be large enough
objects, but they may still be large enough that resolution that resolution to a hierarchical system is appropriate.
to a hierarchical system is appropriate.
In addition, the materials identified by an ISSN, ISBN or In addition, the materials identified by an ISSN, ISBN or
SICI may exist only in printed or other physical form, not SICI may exist only in printed or other physical form, not
electronically. The best that a resolver may be able to electronically. The best that a resolver may be able to
offer is information about where to get the physical offer is information about where to get the physical
resource, such as library holdings or a bookstore or resource, such as library holdings or a bookstore or
publisher order form. The URN Framework provides resolution publisher order form. The URN Framework provides resolution
services that may be used to describe any differences services that may be used to describe any differences
between the resource identified by a URN and the resource between the resource identified by a URN and the resource
that would be returned as a result of resolving that URN. that would be returned as a result of resolving that URN.
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separated by hyphens when printed. The parts are as follows separated by hyphens when printed. The parts are as follows
(in this order): (in this order):
* a group identifier which specifies a group of publishers, * a group identifier which specifies a group of publishers,
based on national, geographic or some other criteria, based on national, geographic or some other criteria,
* the publisher identifier, * the publisher identifier,
* the title identifier, * the title identifier,
* and a modulus 11 check digit, using X in lieu of 10. * and a modulus 11 check digit, using X instead of 10.
The group and publisher number assignments are managed in The group and publisher number assignments are managed in
such a way that the hyphens are not needed to parse the ISBN such a way that the hyphens are not needed to parse the ISBN
unambiguously into its constituent parts. However, the ISBN unambiguously into its constituent parts. However, the ISBN
is normally transmitted and displayed with hyphens to make is normally transmitted and displayed with hyphens to make
it easy for human beings to recognize these parts without it easy for human beings to recognize these parts without
having to make reference to or have knowledge of the number having to make reference to or have knowledge of the number
assignments for group and publisher identifiers. assignments for group and publisher identifiers.
3.2 Encoding Considerations 3.2 Encoding Considerations and Lexical Equivalance
Embedding ISBNs within the URN framework presents no Embedding ISBNs within the URN framework presents no
particular coding problems, since all of the characters that particular encoding problems, since all of the characters
can appear in an ISBN are valid in the identifier segment of that can appear in an ISBN are valid in the identifier
the URN. %-encoding is never needed. segment of the URN. %-encoding, as described in [MOATS] is
never needed.
Example: URN:ISBN:0-395-36341-1 Example: URN:ISBN:0-395-36341-1
For the ISBN namespace, some additional equivalence rules For the ISBN namespace, some additional equivalence rules
are appropriate. Prior to comparing two ISBN URNs for are appropriate. Prior to comparing two ISBN URNs for
equivalence, it is appropriate to remove all hyphens, and to equivalence, it is appropriate to remove all hyphens, and to
convert any occurrences of the letter X to upper case. convert any occurrences of the letter X to upper case.
3.3 Additional considerations 3.3 Additional considerations
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For the ISBN namespace, some additional equivalence rules For the ISBN namespace, some additional equivalence rules
are appropriate. Prior to comparing two ISBN URNs for are appropriate. Prior to comparing two ISBN URNs for
equivalence, it is appropriate to remove all hyphens, and to equivalence, it is appropriate to remove all hyphens, and to
convert any occurrences of the letter X to upper case. convert any occurrences of the letter X to upper case.
3.3 Additional considerations 3.3 Additional considerations
The ISBN standard and related community implementation The ISBN standard and related community implementation
guidelines define when different versions of a work should guidelines define when different versions of a work should
be assigned the same or differing ISBNs. In actuality, be assigned the same or differing ISBNs. In actuality,
however, practice varies somewhat depending on publisher as however, practice varies somewhat depending on publisher as
to whether different ISBNs are assigned for paperbound vs. to whether different ISBNs are assigned for paperbound vs.
hardbound versions of the same work, electronic vs. printed hardbound versions of the same work, electronic vs. printed
versions of the same work, or versions of the same work
published for example in the US and in Europe. The choice
of whether to assign a new ISBN or to reuse an existing one
when publishing a revised printing of an existing edition of
a work or even a revised edition of a work is somewhat
subjective. Practice varies from publisher to publisher
(indeed, the distinction between a revised printing and a
new edition is itself somewhat subjective). The use of
ISBNs within the URN framework simply reflects these versions of the same work, or versions of the same work
existing practices. Note that it is likely that an ISBN URN distinguished in some other way (e.g.published for example in
will often resolve to many instances of the work (many the US and in Europe). The choice of whether to assign a new
URLs). ISBN or to reuse an existing one when publishing a revised
printing of an existing edition of a work or even a revised
edition of a work is somewhat subjective. Practice varies
from publisher to publisher (indeed, the distinction between
a revised printing and a new edition is itself somewhat
subjective). The use of ISBNs within the URN framework
simply reflects these existing practices. Note that it is
likely that an ISBN URN will often resolve to many instances
of the work (many URLs).
4. International Standard Serials Numbers 4. International Standard Serials Numbers
4.1 Overview 4.1 Overview
International Standard Serials Numbers (ISSN) identify a International Standard Serials Numbers (ISSN) identify a
work that is being published on a continued basis in issues; work that is published on a continued basis in issues; they
they identify the entire (often open-ended, in the case of identify the entire (often open-ended, in the case of an
an actively published) work. ISSNs are defined by the actively published) work. ISSNs are defined by the
standards ISO 3297:1986 [ISO 2] and ISO/DIS 3297 [ISO 3] and international standards ISO 3297:1986 [ISO2] and ISO/DIS
within the United States by NISO Z39.9-1992 [NISO 1]. The 3297 [ISO3] and within the United States by NISO Z39.9-1992
ISSN International Centre is located in Paris and [NISO1]. The ISSN International Centre is located in Paris and coordinates
coordinates a network of regional centers. The National a network of regional centers. The National
Serials Data Program within the Library of Congress is the Serials Data Program within the Library of Congress is the US
US Center of this network. Center of this network.
ISSNs have the form NNNN-NNNN where N is a digit, the last ISSNs have the form NNNN-NNNN where N is a digit, the last
digit may be an upper case X as the result of the check digit may be an upper case X as the result of the check
character calculation. Unlike the ISBN the ISSN components character calculation. Unlike the ISBN the ISSN components
do not have much structure; blocks of numbers are passed out do not have much structure; blocks of numbers are passed out
to the regional centers and publishers. to the regional centers and publishers.
4.2 Encoding Considerations 4.2 Encoding Considerations and Lexical Equivalance
Again, there is no problem representing ISSNs in the Again, there is no problem representing ISSNs in the
namespace-specific string of URNs since all characters valid namespace-specific string of URNs since all characters valid
in the ISSN are valid in the namespace-specific URN string, in the ISSN are valid in the namespace-specific URN string,
and %-encoding is never required. and %-encoding is never required.
Example: URN:ISSN:1046-8188 Example: URN:ISSN:1046-8188
Supplementary comparison rules are also appropriate for the Supplementary comparison rules are also appropriate for the
ISSN namespace. Just as for ISBNs, hyphens should be ISSN namespace. Just as for ISBNs, hyphens should be
dropped prior to comparison and occurrences of 'x' dropped prior to comparison and occurrences of 'x'
normalized to uppercase. normalized to uppercase.
4.3 Additional Considerations 4.3 Additional Considerations
The ISSN standard and related community implementation The ISSN standard and related community implementation
guidelines specify when new ISSNs should be assigned vs. guidelines specify when new ISSNs should be assigned vs.
continuing to use an existing one. There are some continuing to use an existing one. There are some
publications where practice within the bibliographic publications where practice within the bibliographic
community varies from site to site, such as annuals or community varies from institution to insitution, such as
annual conference proceedings. In some cases these are annuals or annual conference proceedings. In some cases
treated as serials and ISSNs are used, and in some cases these are treated as serials and ISSNs are used, and in some
they are treated as monographs and ISBNs are used. For cases they are treated as monographs and ISBNs are used. For
example SIGMOD Record volume 24 number 2 June 1995 contains example SIGMOD Record volume 24 number 2 June 1995 contains
the Proceedings of the 1995 ACM SIGMOD International the Proceedings of the 1995 ACM SIGMOD International
Conference on Management of Data. If you subscribe to the Conference on Management of Data. If you subscribe to the
journal (ISSN 0163-5808) this is simply the June issue. On journal (ISSN 0163-5808) this is simply the June issue. On
the other hand you may have acquired this volume as the the other hand you may have acquired this volume as the
conference proceedings (a monograph) and as such would use conference proceedings (a monograph) and as such would use
the ISBN 0-89791-731-6 to identify the work. There are also the ISBN 0-89791-731-6 to identify the work. There are also
varying practices within the publishing community as to when varying practices within the publishing community as to when
new ISSNs are assigned due to the change in the name of a new ISSNs are assigned due to the change in the name of a
periodical (Atlantic becomes Atlantic Monthly); or when a periodical (e.g. Atlantic becomes Atlantic Monthly); or when
periodical is published both in printed and electronic a periodical is published both in printed and electronic
versions (The New York Times). The use of ISSNs as URNs versions (e.g. The New York Times). The use of ISSNs in URNs
will reflect these judgments and practices. will reflect these judgments and practices.
5. Serial Item and Contribution Identifiers 5. Serial Item and Contribution Identifiers
5.1 Overview 5.1 Overview
The standard for Serial Item and Contribution Identifiers The standard for Serial Item and Contribution Identifiers
(SICI) has recently been extensively revised and is defined (SICI) codes, which has recently been extensively revised,
by NISO/ANSI Z39.56-1997 [NISO 2]. The maintenance agency is defined by NISO/ANSI Z39.56-1997 [NISO2]. The maintenance
for the SICI code is the UnCover Corporation. agency for the SICI code is the UnCover Corporation.
SICI codes can be used to identify an issue of a serial, or SICI codes can be used to identify an issue of a serial, or
a specific contribution (i.e., an article, or the table of a specific contribution (e.g., an article, or the table of
contents) within an issue of a serial. SICI codes are not contents) within an issue of a serial. SICI codes are not
assigned, they are constructed based on information about assigned, they are constructed based on information about
the issue or issue component in question. the issue or issue component in question.
The complete syntax for the SICI code will not be discussed The complete syntax for the SICI code will not be discussed
here; see NISO/ANSI Z39.56-1997 for details. However an here; see NISO/ANSI Z39.56-1997 [NISO2] for details.
example and brief review of the major components is needed However, an example and brief review of the major components
is needed to understand the relationship with the ISSN and
to understand the relationship with the ISSN and how this how this identifier differs from an ISSN. An example of a
identifier differs. An example of a SICI code is: SICI code is: 0015-6914(19960101)157:1<62:KTSW>2.0.TX;2-F
0015-6914(19960101)157:1<62:KTSW>2.0.TX;2-F
The first nine characters are the ISSN identifying the The first nine characters are the ISSN identifying the
serial title. The second component, in parentheses, is the serial title. The second component, in parentheses, is the
chronology information giving the date the particular serial chronology information giving the date the particular serial
issue was published. In this example that date was January issue was published. In this example that date was January
1, 1996. The third component, 157:1, is enumeration 1, 1996. The third component, 157:1, is enumeration
information (volume, number) on the particular issue of the information (volume, number) for the particular issue of the
serial. These three components comprise the "item segment" serial. These three components comprise the "item segment"
of a SICI code. By augmenting the ISSN with the chronology of a SICI code. By augmenting the ISSN with the chronology
and/or enumeration information, specific issues of the and/or enumeration information, specific issues of the
serial can be identified. The next segment, <62:KTSW>, serial can be identified. The next segment, <62:KTSW>,
identifies a particular contribution within the issue. In identifies a particular contribution within the issue. In
this example we provide the starting page number and a title this example we provide the starting page number and a title
code constructed from the initial characters of the title. code constructed from the initial characters of the title.
Identifiers assigned to a contribution can be used in the Identifiers assigned to a contribution can be used in the
contribution segment if page numbers are inappropriate. The contribution segment if page numbers are inappropriate. The
rest of the identifier is the control segment, which rest of the identifier is the control segment, which
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of a SICI code. By augmenting the ISSN with the chronology of a SICI code. By augmenting the ISSN with the chronology
and/or enumeration information, specific issues of the and/or enumeration information, specific issues of the
serial can be identified. The next segment, <62:KTSW>, serial can be identified. The next segment, <62:KTSW>,
identifies a particular contribution within the issue. In identifies a particular contribution within the issue. In
this example we provide the starting page number and a title this example we provide the starting page number and a title
code constructed from the initial characters of the title. code constructed from the initial characters of the title.
Identifiers assigned to a contribution can be used in the Identifiers assigned to a contribution can be used in the
contribution segment if page numbers are inappropriate. The contribution segment if page numbers are inappropriate. The
rest of the identifier is the control segment, which rest of the identifier is the control segment, which
includes a check character. Interested readers are includes a check character. Interested readers are
encouraged to consult the standard for an explanation of the encouraged to consult the standard for an explanation of the
fields in that segment. fields in that segment.
5.2 Encoding Considerations 5.2 Encoding Considerations and Lexical Equivalance
The character set for SICIs is intended to be email- The character set for SICIs is intended to be email-
transport-transparent, so it does not present major transport-transparent, so it does not present major problems.
problems. However, all printable excluded and reserved However, all printable excluded and reserved characters from
characters from the URN syntax draft are valid in the SICI the URN syntax are valid in the SICI character set and must
character set and must be %-encoded. be %-encoded.
Example of a SICI for an issue of a journal Example of a SICI for an issue of a journal:
URN:SICI:1046-8188(199501)13:1%3C%3E1.0.TX;2-F URN:SICI:1046-8188(199501)13:1%3C%3E1.0.TX;2-F
For an article contained within that issue For an article contained within that issue:
URN:SICI:1046-8188(199501)13:1%3C69:FTTHBI%3E2.0.TX;2-4 URN:SICI:1046-8188(199501)13:1%3C69:FTTHBI%3E2.0.TX;2-4
Special equivalence rules for SICIs are not appropriate for Equivalence rules for SICIs are not appropriate for
definition as part of the namespace and incorporation in definition as part of the namespace and incorporation in
areas such as cache management algorithms. These are best areas such as cache management algorithms. It is best left
left to resolver systems which try to determine if two SICIs to resolver systems which try to determine if two SICIs refer
refer to the same content. Consequently, we do not propose to the same content. Consequently, we do not propose any
any specific rules for equivalence testing through lexical specific rules for equivalence testing through lexical manipulation.
manipulation.
5.3 Additional Considerations 5.3 Additional Considerations
Since the serial is identified by an ISSN, some of the Since the serial is identified by an ISSN, some of the
ambiguity currently found in the assignment of ISSNs carries ambiguity currently found in the assignment of ISSNs carries
over into SICI codes. In cases where an ISSN may refer to a over into SICI codes. In cases where an ISSN may refer to a
serial that exists in multiple formats, the SICI contains a serial that exists in multiple formats, the SICI contains a
qualifier that specifies the format type (for example, qualifier that specifies the format type (for example,
print, microform, or electronic). SICI codes may be print, microform, or electronic). SICI codes may be
constructed from a variety of sources (the actual issue of constructed from a variety of sources (the actual issue of
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volume, issue and page number), another code might be volume, issue and page number), another code might be
constructed based only on enumeration information and constructed based only on enumeration information and
without benefit of chronology. Systems that use SICI codes without benefit of chronology. Systems that use SICI codes
employ complex matching algorithms to try to match SICI employ complex matching algorithms to try to match SICI
codes constructed from incomplete information to SICI codes codes constructed from incomplete information to SICI codes
constructed with the benefit of all relevant information. constructed with the benefit of all relevant information.
6. Security Considerations 6. Security Considerations
This document proposes means of encoding several existing This document proposes means of encoding several existing
bibliographic identifiers within the URN framework. It does bibliographic identifiers within the URN framework. This
not discuss resolution; thus questions of secure or documentent does not discuss resolution; thus questions of
authenticated resolution mechanisms are out of scope. It secure or authenticated resolution mechanisms are out of
does not address means of validating the integrity or scope. It does not address means of validating the integrity
authenticating the source or provenance of URNs that contain or authenticating the source or provenance of URNs that
bibliographic identifiers. Issues regarding intellectual contain bibliographic identifiers. Issues regarding
property rights associated with objects identified by the intellectual property rights associated with objects
various bibliographic identifiers are also beyond the scope identified by the various bibliographic identifiers are also
of this document, as are questions about rights to the beyond the scope of this document, as are questions about
databases that might be used to construct resolvers. rights to the databases that might be used to construct
resolvers.
7. References 7. References
[ISO1] NISO/ANSI/ISO 2108:1992 Information and documentation [ISO1] NISO/ANSI/ISO 2108:1992 Information and documentation
-- International standard book number (ISBN) -- International standard book number (ISBN)
[ISO2] ISO 3297:1986 Documentation -- International standard [ISO2] ISO 3297:1986 Documentation -- International standard
serial numbering (ISSN) serial numbering (ISSN)
[ISO3] ISO/DIS 3297 Information and documentation -- [ISO3] ISO/DIS 3297 Information and documentation --
International standard serial numbering (ISSN) International standard serial numbering (ISSN)
(Revision of ISO 3297:1986) (Revision of ISO 3297:1986)
[Moats] R. Moats, "URN Syntax" draft-ietf-urn-syntax-
[Moats] R. Moats, URN Syntax RFC 2141 May 1997.
[NISO 1] NISO/ANSI Z39.9-1992 International standard serial [NISO 1] NISO/ANSI Z39.9-1992 International standard serial
numbering (ISSN) numbering (ISSN)
[NISO 2] NISO/ANSI Z39.56-1997 Serial Item and Contribution [NISO 2] NISO/ANSI Z39.56-1997 Serial Item and Contribution
Identifier Identifier
[Sollins & Masinter] K. Sollins and L. Masinter, "Functional [Sollins & Masinter] K. Sollins and L. Masinter, "Functional
Requirements for Uniform Resource Names", RFC 1737 Requirements for Uniform Resource Names", RFC 1737
December 1994. December 1994.
8. Author's Addresses 8. Author's Addresses
Clifford Lynch Clifford Lynch
University of California Office of the President Executive Director
300 Lakeside Drive, 8th floor Coalition for Networked Information
Oakland CA 94612-3550 21 Dupont Circle
clifford.lynch@ucop.edu Washington, DC 20036
cliff@cni.org
Cecilia Preston Cecilia Preston
Preston & Lynch Preston & Lynch
PO Box 8310 PO Box 8310
Emeryville, CA 94662 Emeryville, CA 94662
cecilia@well.com cecilia@well.com
Ron Daniel Jr. Ron Daniel Jr.
Advanced Computing Lab, MS B287 Advanced Computing Lab, MS B287
Los Alamos National Laboratory Los Alamos National Laboratory
Los Alamos, NM, 87545 Los Alamos, NM, 87545
voice: +1 505 665 0597 rdaniel@acl.lanl.gov
fax: +1 505 665 4939
http://www.acl.lanl.gov/~rdaniel
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