ISO/IEC/IEEE FDIS 15026-1

ISO/IEC /JTC 1/SC 7 N9752
Secretariat: BIS
Date: 2025-07-04-15
Systems and software engineering — Systems and software
assurance —
Part 1: Concepts
Vocabulary and vocabularyconcepts
Ingénierie des systèmes et du logiciel — Assurance des systèmes et du logiciel — —
Partie 1: ConceptsVocabulaire et vocabulaireconcepts
FDIS stage
ISO/IEC/IEEE CDFDIS 15026–-1
:20xx(E:2025(en)
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
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Published in Switzerland.
© ISO/IEC/IEEE 20xx 2025 – All rights reserved
ii
Contents Page
Foreword . iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms related to assurance . 1
3.2 Terms related to system life cycles . 5
3.3 Terms related to integrity level . 6
3.4 Terms related to risks and dependability . 7
4 Basic concepts . 11
4.1 General . 11
4.2 Assurance . 11
4.3 Stakeholders . 12
4.4 System and product . 12
4.5 Property . 12
4.6 Uncertainty and confidence . 13
4.7 Conditions and initiating events . 13
4.8 Consequences . 14
5 Using multiple parts of the ISO/IEC/IEEE 15026 series . 15
5.1 General . 15
5.2 Initial usage guidance. 15
5.3 Relationships among parts of the ISO/IEC/IEEE 15026 series . 15
5.4 Authorities . 15
6 The ISO/IEC/IEEE 15026 series and the assurance case . 16
6.1 General . 16
6.2 Justification of method of reasoning . 16
6.3 Means of obtaining and managing evidence . 17
6.4 Certifications and accreditations . 18
7 The ISO/IEC/IEEE 15026 series and integrity levels . 18
7.1 General . 18
7.2 Risk analysis . 18
8 The ISO/IEC/IEEE 15026 series and the life cycle . 19
8.1 General . 19
8.2 Assurance activities in the life cycle . 20
Bibliography . 21
IEEE notices and abstract . 28

© ISO/IEC 2025, © /IEEE 2025 – All rights reserved
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ISO/IEC/IEEE CDFDIS 15026–-1
:20xx(E:2025(en)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members
of ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work.
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
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 or www.iec.ch/members_experts/refdocs).
IEEE Standards documents are developed within the IEEE Societies and the Standards Coordinating
Committees of the IEEE Standards Association (IEEE-SA) Standards Board. The IEEE develops its standards
through a consensus development process, approved by the American National Standards Institute, which
brings together volunteers representing varied viewpoints and interests to achieve the final product.
Volunteers are not necessarily members of the Institute and serve without compensation. While the IEEE
administers the process and establishes rules to promote fairness in the consensus development process, the
IEEE does not independently evaluate, test, or verify the accuracy of any of the information contained in its
standards.
ISO and IEC draw attention to the possibility that the implementation of this document may involve the use of
(a) patent(s). ISO and IEC take no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO and IEC had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent database
available at www.iso.org/patents and https://patents.iec.ch. ISO and IEC shall not be held responsible for
identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 7, Software and systems engineering, in cooperation with the Systems and Software
Engineering Standards Committee of the IEEE Computer Society, under the Partner Standards Development
Organization cooperation agreement between ISO and IEEE.
This second edition cancels and replaces the first edition (ISO/IEC/IEEE 15026-1:2019), which has been
technically revised.
The main changes are as follows:
© ISO/IEC/IEEE 20xx 2025 – All rights reserved
iv
— — definitions of terms introduced in other parts of the ISO/IEC/IEEE 15026 series have been added or
modified;
— — definitions of terms whose definitions were sourced from ISO/IEC 15288 and ISO/IEC/IEEE 24774
have been updated.
A list of all parts in the ISO/IEC/IEEE 15026 series can be found on the ISO website and IEC websites.
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 and www.iec.ch/national-
committees.
© ISO/IEC 2025, © /IEEE 2025 – All rights reserved
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ISO/IEC/IEEE CDFDIS 15026–-1
:20xx(E:2025(en)
Introduction
Software and systems assurance and closely related fields share concepts but have different vocabularies and
perspectives. This document provides an unambiguous use of vocabulary for systems and software assurance
and a unifying set of underlying concepts across these various fields. It provides a basis for elaboration,
discussion and recording agreement and rationale regarding concepts and the vocabulary used uniformly
across the ISO/IEC/IEEE 15026. series.
Clause 4Clause 4 of this document covers basic concepts such as assurance, stakeholders, systems and
products, property, uncertainty and confidence, conditions and initial events, and consequence.
Clause 5Clause 5 covers some issues of which users of ISO/IEC/IEEE 15026-2, ISO/IEC/IEEE 15026-3 and
ISO/IEC/IEEE 15026-4 should be initially aware (5.2). Clause 6(5.2). Clause 6, Clause 7, Clause 7 and
Clause 8Clause 8, respectively, cover concepts and relevant to users of ISO/IEC/IEEE 15026-2,
ISO/IEC/IEEE 15026-3 and ISO/IEC/IEEE 15026-4, respectively; also, users of one of these parts can benefit
from the clauses for other parts.
The essential concepts introduced by the ISO/IEC/IEEE 15026 series are the claims in an assurance case and
the support of claims in terms of argument and evidence. These claims are in the context of assurance for
properties of systems and software within life cycle processes for the system or software product.
Potential users of the ISO/IEC/IEEE 15026 series are developers and maintainers of assurance cases and those
who wish to develop, sustain, evaluate or acquire a system that possesses requirements for specific properties
in such a way as to be more certain of those properties and their requirements. The ISO/IEC/IEEE 15026
series uses concepts and vocabulary consistent with ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288 and
generally consistent with the standards on Systems and software Quality Requirements and Evaluation
(SQuaRE) developed by JTC 1/SC 7, but the concepts and vocabulary provided by the ISO/IEC/IEEE 15026 (all
parts)series can differ from those to which the potential user is accustomed. This document attempts to clarify
these differences.
The ISO/IEC/IEEE 15026 series is made up of the following parts.
— — ISO/IEC/IEEE 15026-1 explains concepts and terms as a basis for all parts of the ISO/IEC/IEEE 15026
series.
— — ISO/IEC/IEEE 15026-2 includes requirements on the structure of the assurance case.
— — ISO/IEC/IEEE 15026-3 relates integrity levels to the assurance case and includes requirements for
their use with and without an assurance case.
— — ISO/IEC/IEEE 15026-4 provides guidance and recommendations for assurance of a selected claim
about the system-of-interest by achieving the claim and showing the achievement. The guidance and
recommendations are given in a system assurance process view on top of ISO/IEC/IEEE 15288 and a
software assurance process view on top of ISO/IEC/IEEE 12207.
The assurance case is relevant to a greater or lesser extent in all parts of the ISO/IEC/IEEE 15026 series,
although ISO/IEC/IEEE 15026-4 discusses achieving the claim and showing the achievement of the claim
whether or not such “showing” is contained in an artefact specifically called an “assurance case”.
© ISO/IEC/IEEE 20xx 2025 – All rights reserved
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