ISO/TS 22943

© ISO 2021 – All rights reserved
ISO NP PDTS/PRF TS 22943:202#(X2022(E)
ISO TC 46/SC 9/WG 16
Date: 2022-04-27
Secretariat: ANSI
Information and documentation — Principles of identification
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This document is not an ISO International Standard. It is distributed for review and comment. It is subject to

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of

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mechanical, including photocopying, or posting on the internet or an intranet, without prior written

permission. Permission can be requested from either ISO at the address below or ISO’sISO's member body in

Foreword .............................................................................................................................................................. vii

Introduction .......................................................................................................................................................... ix

1 Scope .......................................................................................................................................................... 1

2 Normative references .......................................................................................................................... 1

3 Terms and definitions .......................................................................................................................... 1

4 Optimal attributes of identifiers and identifier systems ........................................................ 4

4.1 Uniqueness ............................................................................................................................................... 4

4.2 Persistence ............................................................................................................................................... 4

4.3 Granularity of the identifier to suit the needs of the sector ................................................... 5

4.4 Stability of kernel metadata .............................................................................................................. 5

4.5 No ambiguity within its own namespace ...................................................................................... 6

4.6 Access ......................................................................................................................................................... 6

4.7 Scope .......................................................................................................................................................... 6

4.8 Absence of semantics in identifier strings .................................................................................... 6

4.9 Resolution ................................................................................................................................................ 7

4.10 Timing of assignment ........................................................................................................................... 7

4.11 Resilience in the face of errors ......................................................................................................... 7

4.12 Economic sustainability of the identifier system ....................................................................... 7

4.13 Trustworthiness ..................................................................................................................................... 7

5 Bibliography ............................................................................................................................................ 9

Foreword ................................................................................................................................................................iv

Introduction ........................................................................................................................................................... v

1 Scope .......................................................................................................................................................... 1

2 Normative references .......................................................................................................................... 1

3 Terms and definitions .......................................................................................................................... 1

4 Optimal attributes of identifiers and identifier systems ........................................................ 4

4.1 Uniqueness ............................................................................................................................................... 4

4.2 Persistence ............................................................................................................................................... 4

4.3 Granularity of the identifier to suit the needs of the sector ................................................... 5

4.4 Stability of kernel metadata .............................................................................................................. 5

4.5 No ambiguity within its own namespace ...................................................................................... 5

4.6 Access ......................................................................................................................................................... 6

4.7 Scope .......................................................................................................................................................... 6

4.8 Absence of semantics in identifier strings .................................................................................... 6

4.9 Resolution ................................................................................................................................................ 7

4.10 Timing of assignment ........................................................................................................................... 7

4.11 Resilience in the face of errors ......................................................................................................... 7

4.12 Economic sustainability of the identifier system ...................................................................... 7

4.13 Trustworthiness .................................................................................................................................... 7

5 Bibliography ........................................................................................................................................... 9

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

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committee has been established has the right to be represented on that committee. International

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described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives 2 (see

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any

patent rights identified during the development of the document will be in the Introduction and/or on

the ISO list of patent declarations received (see www.iso.org/patentswww.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

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Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

This document was prepared by Technical Committee ISO/TC 46, Information and documentation,

Any feedback or questions on this document should be directed to the user’s national standards body. A

ISO/TC46/SC9 is the ISO subcommittee on Identificationidentification and description that creates

standards for content identifiers, description and associated metadata and models for use in information

organizations, including libraries, museums and archives, and the content industries, including

publishing and other content producers and providers under the auspices of ISO Technical Committee 46

on Information and documentation. The Committeecommittee is responsible for a suite of identifier

standards, including the International Standard Book Number (ISBN), the International Standard Serial

Number (ISSN), the International Standard Name Identifier (ISNI), the International Standard Recording

Code (ISRC), the International Standard Audiovisual Number (ISAN), the Digital Object Identifier (DOI),

the International Standard Link Identifier (ISLI), International Musical Work Code (ISWC), among several

other standards. It also oversees the numerous registration authorities that manage these identifier

Identification systems, as defined in this document, create concise codes (“identifiers”) that can be used

to refer unambiguously to something or someone (the “referent”). In this way, the identifier can be

provided as a proxy for the referent itself, for instance in cataloguing it in a library, enquiring about its

attributes, ordering a copy of it or (if a person or party) attributing authorship in something. To be useful

an identification system should be built upon trust in a variety of its characteristics. These include the

reliability of the binding between identifier and the referent, trust in the assignment of the identifier, the

related metadata, the longevity of the identification system, and the extent of the system’s use in its sector.

This document describes the characteristics of identification systems that provide this trust to meet the

needs of particular use cases and have other characteristics that make them useful in real world

Having an identifier opens the possibility to access trusted information about the referent as well as to

facilitate services that use the identifier. These related metadata mightcan include information about the

referent, such as rights or pricing information or connected information such as creators or derivatives.

Services mightcan include more efficient data exchange, order processing, or discovery. Services can even

Identification systems are built upon trust among parties in the supply chain of information about a

referent. Where the trust in the identifier has been generated by appropriate technologies, policies, and

governance, then the value of systems which use it is increased as they enable the curation, discovery,

commercial exploitation and preservation of the referents to which an identification system has been

applied. This value comes about through increased efficiency for all participants in the ecosystem. There

are a number of ways in which the binding between the identifier and the referent can be made

trustworthy. This begins with the source of the data and it being recognized as a canonical source of data

about the referent. This is further supported by consensus and engagement of the community of

implementers and users of the identifier and its related data. The ability of the system to provide data

reliably and in ways that users of the identification system require enhances this trust. The viability of

the system and its ability to persist, both financially and technologically, buttress the community’s

A core function of an identification system is to draw a distinction between referents. Referents may often

be similar and share common attributes. What distinguishes one referent from another is often defined

by the use cases that are described by the identifier standard. Clear assignment rules, i.e.,. the

specifications for when a "thing" is the same as another "thing" and when they are different, are a critical

component of any identification system. Any community of practice should carefully consider, and be

appropriately cautious in adopting, any proposal that increases the number of identifiers used to deal

with similar populations of referents. The costs of management escalate with the number of identifiers

assigned and finer granularity may, unless clearly justified, increase costs both for the system and for

users who need to deal with multiple identifiers to specify what they otherwise regard as a single

The following are two examples of identifiers and some of their associated kernel metadata:.

The examples noted abovegiven adhere to many of the core principles of identification system described

in this document. Both identifiers are globally unique in a sizable namespace that can cover more than

the potential items in its conceivable universe. The identifier examples complyis in accordance with a

variety of underlying standards about structure, and additional referencing standards. Outside of any

relevant context, the identifier string itself is devoid of meaning. But within the context of a broader

identification system, by being attached with a prefix, an appropriate display, or field heading, the string

then becomes bound to a wealth of additional information that exists about the referent. It is not the

string of characters, per se, that makes an identifier valuable, it is that associated metadata and the

broader identification system that bind the identifier together in the ecosystem to create value. There is

also a certain synergy if the attributes themselves are (or can be associated with) other identifiers −− this

contributes to the ‘"web of identifiers’identifiers" and enables further discovery (e.g.,. contributors

associated with an ISBN or ISAN may themselves be identified via ISNI, such as noted in the ISAN

These systems require a great deal of infrastructure and investment to manage the information, including

the assignment process, the curation efforts, the technical systems, and the maintenance of the entire

system as community needs grow over time. The principles described in this document help support

NOTE: In some cases, identifier systems might not include all the attributes or characteristics described

in this document. Not all of these attributes need apply in every circumstance. Furthermore, it is

understood that there are some elements of these principles which may not be operable in existing or

future systems and a lack of conformance with these principles should be evaluated on its merits within

that system and its own context. For example, there are a variety of distributed identifier systems that

have wide adoption, such as URN or URI, which do not involve centralized management of the

This document defines the philosophy of why identifiers exist and why they are valuable for trade and

information management. It establishes a core set of relevant characteristics and expectations for

identifiers and the general business case of guidelines for identifiers. This document explains the reason

identifiers are structured the way they are and for what purpose, while acknowledging other

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp

— IEC Electropedia: available at http://www.electropedia.org/https://www.electropedia.org/

characteristics of a referent (3.16) that describe and disambiguate it from any other referent (3.16) within

Note 1 to entry: An attribute may be common to other referents (3.16) and relate them for a specific purpose.

Note 2 to entry: A particular referent’s (3.16) attributes, and, in particular, their distinction from those attributes

should make the referent (3.16) globally unique within that identifier system (3.9).

Note 1 to entry: This binding may be represented by metadata (3.12) recording the relevant attributes (3.1) of the

Note 2 to entry: The binding mechanism may be explicit (recorded in an authoritative database) or implicit (derived

Note 1 to entry: This couldcan include bringing together stakeholders involved in the use of the identifier (3.5) for

the purposes of establishing rules for the assignment of identifiers (3.5) and requirements for associated metadata

(3.12), overseeing the process of assignment, monitoring the system for issues, managing conflict resolution, and

Note 1 to entry: The granularity of an identifier system (3.9) determines when entities are regarded as the same