ISO 20271-1

ISO/DISPRF 20271-1:2026(en)
ISO/TC 171/SC 2
Secretariat: ANSI
Date: 2026-03-1308-19
Document management — Reference model for long-term
preservation of textual document - documents —
Part 1:
Overview
Gestion des documents — Modèle de référence pour une conservation à long terme des documents textuels —
Partie 1: Vue d'ensemble
PROOF
ISO/PRF 20271-1:2026(en)
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Published in Switzerland
-1 2026 – All rights reserved
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ISO/DISPRF 20271-1:2026(en)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Summary of the ISO 20271 series . 2
4.1 General. 2
4.2 Summary of ISO 20271-2: Fundamental . 4
4.3 Summary of the ISO 20271-3: Taxonomy and markup . 4
4.4 Preservation assessment methodology . 4
5 Applicable document types for ISO 20271 series . 4
6 Exploring applicability and extension to additional document types . 5
7 Audience of the ISO 20271 series . 5
Bibliography . 7

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ISO/PRF 20271-1:2026(en)
Foreword
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 through
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The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
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This document was prepared by Technical Committee ISO/TC 171, Document management applications,
Subcommittee SC 2, Document file formats, EDMS systems and authenticity of information.
A list of all parts in the ISO 20271 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

-1 2026 – All rights reserved
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ISO/DISPRF 20271-1:2026(en)
Introduction
Digital document files vary greatly in type and complexity. They range from simple binary stream files to text-
based files readable by humans, machine-interpretable files, and files that, while human-readable, require
interpretation and re-expression through complex logical structures and relationships.
Textual document file formats can take various forms, including simple binary or text-based structures and
more complex packaged formats that encapsulate multiple components, such as content, metadata and
resources, within a single container structure. Many modern document formats adopt such packaged formats.
Ensuring long-term preservation and accessibility of these digital documents can be challenging, primarily
due to technical obsolescence, format incompatibilities, or software/hardware dependencies, such as:
— — file format compatibility issues:
— Filefile formats are no longer supported;
— Newnew software fails to open correctly files created by the older versions of the same software (no
backward compatibility);
— Reliancereliance on proprietary formats rather than on standardized open formats can increase the
risk of format obsolescence and make preservation efforts more challenging e.g. due to inaccessibility
of detailed specifications, unavailability of usable software for handling the formats, or IPR-related
issues;
—
— — limited adoption and support of formats:
— Formatsformats are not widely used or supported in the relevant domain;
— Formatsformats lack an active user community or support from multiple vendors;
NOTE — 1 The use of formats that are widely adopted, based on open specifications, and supported by multiple vendors
can reduce the risk of obsolescence.
— — software and hardware dependencies:
— Filesfiles can only be opened on specific operating systems or software versions;
— Compressioncompression algorithms, encryption technologies or cryptography-based features used
(including digital signatures, seals and time stamps) are no longer supported;
—
— — lack of preservation policies:
— Absenceabsence of policies or processes for the long-term preservation of document files;
— Insufficientinsufficient ongoing monitoring of file formats and storage media management.
NOTE 1 2 Other operational issues such as media ageing, physical corruption, environmental factors, and backup
planning are outside the scope of the ISO 20271 series.
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ISO/PRF 20271-1:2026(en)
The ISO 20271 series defines technical methods for the selection, verification and assessment of the subjects
of technical review concerning the obsolescence of textual documents. It provides a reference model and
framework for understanding textual documents and the properties that maycan be present within them. The
reference model addresses technical issues and provides assessment criteria to determine which digital
components (layers) or metadata are desirable or necessary for long-term preservation, as well as to evaluate
the suitability format for this purpose. To support this, the ISO 20271 series is structured as follows (see
Figure 1Figure 1):):
— — This document (ISO 20271-1) defines the overall framework, scope and principles for the technical
review of textual document formats in the context of obsolescence. It also provides an explanation of the
structure and scope of the ISO 20271 series to enhance users’ understanding.
— — ISO 20271-2 defines a reference model for textual document formats that can be used to analyse a
textual document file format. It also provides recommendations for preserving each layer of the format,
including content, metadata and presentation, ensuring long-term accessibility and integrity of the
document.
— — ISO 20271-3 (under development) is intended to specify3specifies properties that can exist in a textual
document and provides reference markup for representing those properties.
The ISO 20271 series is intended for use by organizations and practitioners involved in the creation,
management and preservation of textual documents. This includes developers of document formats, system
architects, archivists, and other stakeholders responsible for ensuring long-term accessibility and
sustainability.
The ISO 20271 series supports activities such as the analysis of textual document formats, the identification
and classification of document properties, the definition of preservation requirements, and the assessment of
long-term preservation risks.
In practice, the ISO 20271 series is intended to be applied as a coherent and iterative process.
ISO 20271-2 provides a reference model for analysing textual document formats by identifying layers and
associated properties.
ISO 20271-3 builds upon this model by defining a taxonomy for classifying these properties and by providing
non-prescriptive examples of how such properties maycan be represented.
Together, these parts support a structured approach to the analysis, description, and evaluation of textual
document formats in the context of long-term preservation.
Within the reference model, characteristics of textual documents are expressed as properties.
These properties may be associated with one or more layers and form the basis for classification, analysis, and
preservation assessment across the ISO 20271 series.
Some parts of the ISO 20271 series are currently under development or planned, and references to these part
...