Open systems dependability

IEC 62853:2018 provides guidance in relation to a set of requirements placed upon system life cycles in order for an open system to achieve open systems dependability. This document elaborates on IEC 60300-1 by providing details of the changes needed to accommodate the characteristics of open systems. It defines process views based on ISO/IEC/IEEE 15288:2015, which identifies the set of system life cycle processes. This document is applicable to life cycles of products, systems, processes or services involving hardware, software and human aspects or any integrated combinations of these elements. For open systems, security is especially important since the systems are particularly exposed to attack. This document can be used to improve the dependability of open systems and to provide assurance that the process views specific to open systems achieve their expected outcomes. It helps an organization define the activities and tasks that need to be undertaken to achieve dependability objectives in an open system, including dependability related communication, dependability assessment and evaluation of dependability throughout system life cycles. Keywords: dependability of open systems

Zuverlässigkeit offener Systeme

Sûreté de fonctionnement des systèmes ouverts

IEC 62853:2018 fournit des recommandations relatives à un ensemble d'exigences portant sur les cycles de vie des systèmes et visant à assurer la sûreté de fonctionnement des systèmes ouverts. Le présent document précise l'IEC 60300-1 en fournissant des détails sur les changements nécessaires pour s'adapter aux caractéristiques des systèmes ouverts. Il définit les vues de processus basées sur l'ISO/IEC/IEEE 15288:2015, qui identifie l'ensemble des processus du cycle de vie du système. Le présent document est applicable au cycle de vie des produits, des systèmes, des processus ou des services impliquant des aspects matériels, logiciels et humains ou toute combinaison intégrant ces éléments. La sécurité des systèmes ouverts est particulièrement importante, car ces systèmes sont fortement exposés aux attaques des logiciels malveillants. Le présent document peut être utilisé pour améliorer la sûreté de fonctionnement des systèmes ouverts et pour garantir que les vues de processus spécifiques aux systèmes ouverts donnent les résultats escomptés. Il aide les organismes à définir les activités et les tâches qui doivent être entreprises pour atteindre les objectifs de sûreté de fonctionnement dans un système ouvert, y compris en matière de communication relative à la sûreté de fonctionnement, ainsi que d'appréciation et d'évaluation de la sûreté de fonctionnement tout au long du cycle de vie du système. Mots clés: sûreté de fonctionnement des systèmes ouverts

Odprti sistemi zanesljivosti (IEC 62853:2018)

Ta dokument podaja smernice v zvezi z nizom zahtev glede življenjskih ciklov sistemov, da bi odprti sistem dosegel zanesljivost odprtega sistema.
Ta dokument dopolnjuje standard IEC 60300-1 z navedbo podrobnosti o potrebnih spremembah, ki ustrezajo lastnostim odprtih sistemov. Opredeljuje procesne vidike na podlagi standarda ISO/IEC/IEEE 15288:2015, ki določa nabor procesov življenjskega cikla sistema.
Ta dokument se uporablja za življenjske cikle proizvodov, sistemov, procesov ali storitev, ki vključujejo strojno opremo, programsko opremo in človeške vidike ali poljubno integrirano kombinacijo teh elementov. Varnost je pri odprtih sistemih še posebej pomembna, saj so sistemi običajno izpostavljeni napadom.
Ta dokument se lahko uporablja za povečanje zanesljivosti odprtih sistemov in zagotovitev, da procesni vidiki, ki so specifični za odprte sisteme, dosežejo pričakovane rezultate. Organizaciji pomaga opredeliti dejavnosti in naloge, potrebne za doseganje ciljev glede zanesljivosti odprtega sistema, vključno s komunikacijo, povezano z zanesljivostjo, oceno zanesljivosti in vrednotenjem zanesljivosti v celotnem življenjskem ciklu sistema.

General Information

Status
Published
Publication Date
04-Oct-2018
Technical Committee
Drafting Committee
Current Stage
6060 - Document made available
Due Date
05-Oct-2018
Completion Date
05-Oct-2018

Buy Standard

Standard
EN IEC 62853:2018 - BARVE na PDF-str 56
English language
74 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN IEC 62853:2018
01-december-2018
Odprti sistemi zanesljivosti (IEC 62853:2018)
Open systems dependability (IEC 62853:2018)
Ta slovenski standard je istoveten z: EN IEC 62853:2018
ICS:
03.100.40 Raziskave in razvoj Research and development
03.120.01 Kakovost na splošno Quality in general
21.020 =QDþLOQRVWLLQQDþUWRYDQMH Characteristics and design of
VWURMHYDSDUDWRYRSUHPH machines, apparatus,
equipment
SIST EN IEC 62853:2018 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN IEC 62853:2018
---------------------- Page: 2 ----------------------
SIST EN IEC 62853:2018
EUROPEAN STANDARD EN IEC 62853
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2018
ICS 03.100.40; 03.120.01; 21.020
English Version
Open systems dependability
(IEC 62853:2018)
Sûreté de fonctionnement des systèmes ouverts Zuverlässigkeit offener Systeme
(IEC 62853:2018) (IEC 62853:2018)

This European Standard was approved by CENELEC on 2018-07-18. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,

Switzerland, Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 62853:2018 E
---------------------- Page: 3 ----------------------
SIST EN IEC 62853:2018
EN IEC 62853:2018 (E)
European foreword

The text of document 56/1772/FDIS, future edition 1 of IEC 62853, prepared by IEC/TC 56

"Dependability" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as

EN IEC 62853:2018.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2019-04-18

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2021-07-18

document have to be withdrawn

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

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice

The text of the International Standard IEC 62853:2018 was approved by CENELEC as a European

Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards

indicated:
ISO 22301:2012 NOTE Harmonized as EN ISO 22301:2014 (not modified)
ISO 9000:2015 NOTE Harmonized as EN ISO 9000:2015 (not modified)
IEC 62741 NOTE Harmonized as EN 62741
---------------------- Page: 4 ----------------------
SIST EN IEC 62853:2018
EN IEC 62853:2018 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments)

applies.

NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:

www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-192 - International electrotechnical vocabulary - - -
Part 192: Dependability
IEC 60300-1 - Dependability management - Part 1: EN 60300-1 -
Guidance for management and application
ISO/IEC/IEEE 15288 2015 Systems and software engineering – - -
System life cycle processes
---------------------- Page: 5 ----------------------
SIST EN IEC 62853:2018
---------------------- Page: 6 ----------------------
SIST EN IEC 62853:2018
IEC 62853
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Open systems dependability
Sûreté de fonctionnement des systèmes ouverts
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.100.40; 03.120.01; 21.020 ISBN 978-2-8322-5789-0

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN IEC 62853:2018
– 2 – IEC 62853:2018 © IEC 2018
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 7

4 Open systems dependability .......................................................................................... 11

4.1 Open systems ....................................................................................................... 11

4.2 Dependability issues specific to open systems ...................................................... 12

4.3 Objective .............................................................................................................. 12

4.4 Achieving open systems dependability .................................................................. 13

4.5 Relationship to resilience and fault tolerance ........................................................ 13

5 Conformance ................................................................................................................. 14

6 Process views for achieving open systems dependability ............................................... 14

6.1 General ................................................................................................................. 14

6.2 Consensus Building process view ......................................................................... 15

6.2.1 Purpose ......................................................................................................... 15

6.2.2 Outcomes ...................................................................................................... 16

6.2.3 Processes, activities and tasks ...................................................................... 17

6.3 Accountability Achievement process view ............................................................. 20

6.3.1 Purpose ......................................................................................................... 20

6.3.2 Outcomes ...................................................................................................... 21

6.3.3 Processes, activities and tasks ...................................................................... 22

6.4 Failure Response process view ............................................................................. 30

6.4.1 Purpose ......................................................................................................... 30

6.4.2 Outcomes ...................................................................................................... 31

6.4.3 Processes, activities and tasks ...................................................................... 33

6.5 Change Accommodation process view .................................................................. 38

6.5.1 Purpose ......................................................................................................... 38

6.5.2 Outcomes ...................................................................................................... 39

6.5.3 Processes, activities and tasks ...................................................................... 40

Annex A (informative) Example life cycle models with open systems dependability ............. 49

A.1 General ................................................................................................................. 49

A.2 Dependable Engineering for Open Systems (DEOS) life cycle model .................... 49

A.3 Warranty Chain Management (WCM) life cycle model ........................................... 51

Annex B (informative) An example template for dependability cases ................................... 53

B.1 Overview............................................................................................................... 53

B.2 Consensus Building argument ............................................................................... 54

B.3 Accountability Achievement argument ................................................................... 56

B.4 Failure Response argument .................................................................................. 58

B.5 Change Accommodation argument ........................................................................ 61

Annex C (informative) Smart Grid ....................................................................................... 64

C.1 General ................................................................................................................. 64

C.2 Background........................................................................................................... 64

---------------------- Page: 8 ----------------------
SIST EN IEC 62853:2018
IEC 62853:2018 © IEC 2018 – 3 –

C.3 Construction of a smart grid dependability case .................................................... 64

C.3.1 General ......................................................................................................... 64

C.3.2 Steps for construction of a smart grid dependability case............................... 65

C.4 The Change Accommodation cycle ....................................................................... 68

C.5 The Failure Response Cycle ................................................................................. 69

Bibliography .......................................................................................................................... 70

Figure A.1 – DEOS life cycle model ([11], adjusted) .............................................................. 50

Figure A.2 – WCM life cycle model ....................................................................................... 52

Figure B.1 – Overall argument .............................................................................................. 53

Figure B.2 – Consensus Building 1 ....................................................................................... 54

Figure B.3 – Consensus Building 2 ....................................................................................... 55

Figure B.4 – Consensus Building 3 ....................................................................................... 55

Figure B.5 – Accountability Achievement 1 ........................................................................... 56

Figure B.6 – Accountability Achievement 2 ........................................................................... 57

Figure B.7 – Accountability Achievement 3 ........................................................................... 57

Figure B.8 – Accountability Achievement 4 ........................................................................... 58

Figure B.9 – Failure Response 1 ........................................................................................... 59

Figure B.10 – Failure Response 2 ......................................................................................... 59

Figure B.11 – Failure Response 3 ......................................................................................... 60

Figure B.12 – Failure Response 4 ......................................................................................... 60

Figure B.13 – Failure Response 5 ......................................................................................... 61

Figure B.14 – Failure Response 6 ......................................................................................... 61

Figure B.15 – Change Accommodation 1 .............................................................................. 62

Figure B.16 – Change Accommodation 2 .............................................................................. 62

Figure B.17 – Change Accommodation 3 .............................................................................. 63

Figure B.18 – Change Accommodation 4 .............................................................................. 63

---------------------- Page: 9 ----------------------
SIST EN IEC 62853:2018
– 4 – IEC 62853:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPEN SYSTEMS DEPENDABILITY
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international

co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in

addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

may participate in this preparatory work. International, governmental and non-governmental organizations liaising

with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence between

any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses

arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent

rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 62853 has been prepared by IEC technical committee 56:

Dependability.
The text of this International Standard is based on the following documents:
FDIS Report on voting
56/1772/FDIS 56/1776/RVD

Full information on the voting for the approval of this International Standard can be found in the

report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

---------------------- Page: 10 ----------------------
SIST EN IEC 62853:2018
IEC 62853:2018 © IEC 2018 – 5 –

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under “http://webstore.iec.ch” in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The ‘colour inside’ logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct understanding

of its contents. Users should therefore print this document using a colour printer.

---------------------- Page: 11 ----------------------
SIST EN IEC 62853:2018
– 6 – IEC 62853:2018 © IEC 2018
INTRODUCTION

Open systems are systems whose boundaries, functions and structure change over time and

which are recognized and described differently from various points of view. The dependability of

open systems is a key attribute for the life cycle of a system that operates for an extended period

of time in a real-world environment. Open systems dependability is the ability of open systems to

accommodate changes in purpose, objectives, environment and actual performance and to

continuously maintain accountability from stakeholders, in order to provide expected services as

and when required. The attributes of dependability, including availability, reliability,

maintainability and supportability, are the same for open systems as conventional systems but

they have to be considered in the context that no single stakeholder has a full understanding of

the system or its risks.

For open systems, security is especially important since the systems are much exposed to

attack by malware. Since an open system changes continuously through its life, the design

process, e.g. modelled by the spiral product development model, will to some extent continue

during the whole lifetime of the system.

This document elaborates on IEC 60300-1 by providing additional guidance for dependability

management of open systems.

This document provides guidance on open systems dependability by using the four process

views, each of which selects and combines system life cycle processes, activities and tasks of

ISO/IEC/IEEE 15288: 2015.
• Change Accommodation process view;
• Accountability Achievement process view;
• Failure Response process view;
• Consensus Building process view.

A dependability case that assures these process views is crucial for stakeholders to understand

and agree on the boundaries of their responsibilities, to assign accountability for implementation

and to duly manage changes in achieving open systems dependability.

The intended audience for this document ranges from users, owners and customers to

organizations involved in and responsible for ensuring that open systems dependability

requirements are being met. Organizations include all types and sizes of corporations, public

and private institutions such as government agencies, business enterprises and non-profit

associations.
---------------------- Page: 12 ----------------------
SIST EN IEC 62853:2018
IEC 62853:2018 © IEC 2018 – 7 –
OPEN SYSTEMS DEPENDABILITY
1 Scope

This document provides guidance in relation to a set of requirements placed upon system life

cycles in order for an open system to achieve open systems dependability.

This document elaborates on IEC 60300-1 by providing details of the changes needed to

accommodate the characteristics of open systems. It defines process views based on

ISO/IEC/IEEE 15288:2015, which identifies the set of system life cycle processes.

This document is applicable to life cycles of products, systems, processes or services involving

hardware, software and human aspects or any integrated combinations of these elements.

For open systems, security is especially important since the systems are particularly exposed to

attack.

This document can be used to improve the dependability of open systems and to provide

assurance that the process views specific to open systems achieve their expected outcomes. It

helps an organization define the activities and tasks that need to be undertaken to achieve

dependability objectives in an open system, including dependability related communication,

dependability assessment and evaluation of dependability throughout system life cycles.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies.

For undated references, the latest edition of the referenced document (including any

amendments) applies.

IEC 60050-192, International Electrotechnical Vocabulary – Part 192: Dependability (available

at http://www.electropedia.org/)

IEC 60300-1, Dependability management – Part 1: Guidance for management and application

ISO/IEC/IEEE 15288:2015, Systems and software engineering – System life cycle processes

3 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60050-192 and the

following apply.

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

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
accountability

state of being answerable for decisions and activities to the organization’s governing bodies,

legal authorities and, more broadly, its stakeholders
---------------------- Page: 13 ----------------------
SIST EN IEC 62853:2018
– 8 – IEC 62853:2018 © IEC 2018
Note 1 to entry: Accountability includes answerability to society in general.

Note 2 to entry: Description in ISO 26000:2010 [1]: Accountability involves an obligation on management to be

answerable to the controlling interests of the organization and on the organization to be answerable to legal

authorities with regard to laws and regulations. Accountability for the overall impact of its decisions and activities on

society and the environment also implies that the organization’s answerability to those affected by its decisions and

activities, as well as to society in general, varies according to the nature of the impact and the circumstances.

Note 3 to entry: The definition in ISO 15489-1:2001 [2]: principle that individuals, organizations and the community

are responsible for their actions and may be required to explain them to others.
[SOURCE: ISO 26000:2010, 2.1, modified – Notes to entry have been added.]
3.2
assurance case

reasoned, auditable artefact created that supports the contention that its top-level claim (or set

of claims) is satisfied, including systematic argumentation and its underlying evidence and

explicit assumptions that support the claim(s)

Note 1 to entry: An assurance case contains the following and their relationships:

– one or more claims about properties;

– arguments that logically link the evidence and any assumptions to the claim(s);

– a body of evidence and possibly assumptions supporting these arguments for the claim(s);

– justification of choice of top-level claim and the method of reasoning.

Note 2 to entry: An assurance case can be understood as a reasoned and compelling argument, supported by a body

of evidence, that a system, service or organization will operate as intended for a defined application in a defined

environment and defined lifetime.

[SOURCE: ISO/IEC 15026-1:2013 [3], 3.1.3, modified – Note 2 to entry has been added.]

3.3
change accommodation

set of activities which modify and adapt a system to changes in its purpose, objectives,

environment or actual performance that require re-establishment of stakeholders’ consensus on

the system
3.4
consensus

general agreement, characterized by the absence of sustained opposition to substantial issues

by any important part of the concerned interests and by a process that involves seeking to take

into account the views of all parties concerned and to reconcile any conflicting arguments

Note 1 to entry: Consensus need not imply unanimity.
[SOURCE: ISO/IEC Guide 2:2004 [4], 1.7]
3.5
dependability case

evidence-based, reasoned, traceable argument created to support the contention that a defined

system does and/or will satisfy the dependability requirements

Note 1 to entry: A dependability case is an assurance case whose top-level claim is about dependability.

[SOURCE: IEC 62741:2015, 3.1.1, modified – Note 1 to entry has been added.]
3.6
dependability communication

continual and iterative process that a stakeholder conducts to provide, share or obtain

information, and to engage in dialogue with other stakeholders regarding the management of

dependability
---------------------- Page: 14 ----------------------
SIST EN IEC 62853:2018
IEC 62853:2018 © IEC 2018 – 9 –

Note 1 to entry: The role of dependability communication in the management of open systems dependability is not

unlike that of risk communication in risk management.

Note 2 to entry: See the definition of the term “communication and consultation” in ISO Guide 73:2009 [5], 3.2.1.

3.7
environment

context determining the setting and circumstances of all influences upon a system

[SOURCE: ISO/IEC/IEEE 42010:2011 [6], 3.8]
3.8
failure response

set of activities initiated immediately when a failure is predicted or detected in order to prevent

the failure or minimize its effect, to analyse its causes and prevent its recurrence and to fulfil

accountability
3.9
frame of reference

set of conventions for the construction, interpretation and use of documents describing a

common understanding of and explicit agreements on a system, its purpose, objectives,

environment, actual performance, life cycle and changes thereof
3.10
interaction error

error that occurs due to the interactions between items despite each item’s performance

meeting the specification
3.11
monitoring
determining the status of a system, a process or an activity

Note 1 to entry: To determine the status there may be a need to check, supervise or critically observe.

[SOURCE: ISO 22301:2012 [7], 3.29]
3.12
open system

system whose boundaries, functions and structure change over time and is recognized and

described differently from various points of view

Note 1 to entry: Changes include not only adaptation with specific purpose but also spontaneous evolution. For

example, they include spontaneous and uncoordinated changes within a system that spans multiple domains with

different authorities.

Note 2 to entry: An open system’s boundaries, functions and structure are not only changing with time but can be

vague at any point in time and recognized differently by different stakeholders. This refines the definition of system in

IEC 60050-192 for a given level of abstraction and a given viewpoint. A boundary can have a clear definition at one

level of abstraction, but it could become more vague at a more detailed level. The level of details necessary for a

purpose or for a stakeholder need not be predetermined nor guaranteed to be attainable.

Note 3 to entry: An open system exchanges resources over its boundary with other systems or the environment,

possibly changing the boundary itself.
Note 4 to entry: Every substantial system has aspects of both an open system
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.