Dependability management - Part 3-15: Application guide - Engineering of system dependability

IEC 60300-3-15:2009 provides guidance for an engineering system's dependability and describes a process for realization of system dependability through the system life cycle. This standard is applicable to new system development and for enhancement of existing systems involving interactions of system functions consisting of hardware, software and human elements.

Zuverlässigkeitsmanagement – Teil 3-15: Anwendungsleitfaden - Technische Realisierung der Systemzuverlässigkeit

Gestion de la sûreté de fonctionnement - Partie 3-15: Guide d'application - Ingénierie de la sûreté de fonctionnement des systèmes

La CEI 60300-3-15:2009 donnent des lignes directrices pour l'ingénierie de la sûreté de fonctionnement des systèmes et elle décrit un processus de réalisation de la sûreté de fonctionnement tout au long du cycle de vie des systèmes. Cette norme s'applique au développement de nouveaux systèmes et à l'amélioration de systèmes existants impliquant des interactions de fonctions système et consistant en des éléments matériels, logiciels et humains.

Upravljanje zagotovljivosti - 3-15. del: Napotki za tehnično načrtovanje sistema zagotovljivosti (IEC 60300-3-15:2009)

Ta del IEC 60300 podaja smernice za zagotavljanje tehničnih sistemov in opisuje postopek izvedbe sistema zagotovljivosti skozi življenjski krog sistema. Ta standard velja za razvoj novih sistemov in za izboljšanje obstoječih sistemov, vključno z vzajemnim delovanjem sistemskih funkcij, sestavljenih iz strojnih, programskih in človeških elementov. Ta standard prav tako velja za ponudnike podsistemov in dobaviteljev proizvodov, ki iščejo sistemske informacije in kriterije za sistemsko integracijo. Metode in orodja so določena za ocenjevanje sistemov zagotovljivosti in potrditev rezultatov za doseganje ciljev zagotovljivosti.

General Information

Status
Published
Publication Date
03-Dec-2009
Technical Committee
Drafting Committee
Parallel Committee
Current Stage
6060 - Document made available
Due Date
04-Dec-2009
Completion Date
04-Dec-2009

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SLOVENSKI STANDARD
SIST EN 60300-3-15:2010
01-februar-2010
8SUDYOMDQMH]DJRWRYOMLYRVWLGHO1DSRWNL]DWHKQLþQRQDþUWRYDQMHVLVWHPD
]DJRWRYOMLYRVWL ,(&

Dependability management - Part 3-15: Guidance to engineering of system dependability

(IEC 60300-3-15:2009)
Zuverlässigkeitsmanagement - Teil 3-15: Anwendungsleitfaden - Technische
Realisierung der Systemzuverlässigkeit (IEC 60300-3-15:2009)

Gestion de la sûreté de fonctionnement - Partie 3-15: Guide d'application - Ingénierie de

la sûreté de fonctionnement des systèmes (CEI 60300-3-15:2009)
Ta slovenski standard je istoveten z: EN 60300-3-15:2009
ICS:
03.120.01 Kakovost na splošno Quality in general
21.020 =QDþLOQRVWLLQQDþUWRYDQMH Characteristics and design of
VWURMHYDSDUDWRYRSUHPH machines, apparatus,
equipment
SIST EN 60300-3-15:2010 en,fr

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

---------------------- Page: 1 ----------------------
SIST EN 60300-3-15:2010
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SIST EN 60300-3-15:2010
EUROPEAN STANDARD
EN 60300-3-15
NORME EUROPÉENNE
December 2009
EUROPÄISCHE NORM
ICS 03.120.01
English version
Dependability management -
Part 3-15: Application guide -
Engineering of system dependability
(IEC 60300-3-15:2009)
Gestion de la sûreté de fonctionnement - Zuverlässigkeitsmanagement -
Partie 3-15: Guide d'application - Teil 3-15: Anwendungsleitfaden -
Ingénierie de la sûreté de fonctionnement Technische Realisierung der
des systèmes Systemzuverlässigkeit
(CEI 60300-3-15:2009) (IEC 60300-3-15:2009)

This European Standard was approved by CENELEC on 2009-10-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

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

Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

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

Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: Avenue Marnix 17, B - 1000 Brussels

© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 60300-3-15:2009 E
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SIST EN 60300-3-15:2010
EN 60300-3-15:2009 - 2 -
Foreword

The text of document 56/1315/FDIS, future edition 1 of IEC 60300-3-15, prepared by IEC TC 56,

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

EN 60300-3-15 on 2009-10-01
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2010-07-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2012-10-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice

The text of the International Standard IEC 60300-3-15:2009 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:

[1] IEC 61069-1 NOTE Harmonized as EN 61069-1:1993 (not modified).
[2] IEC 62347 NOTE Harmonized as EN 62347:2007 (not modified).
[7] IEC 60300-3-1 NOTE Harmonized as EN 60300-3-1:2004 (not modified).
[9] IEC 61508 NOTE Harmonized in EN 61508 series (not modified).
[10] IEC 61508-1 NOTE Harmonized as EN 61508-1:2001 (not modified).
[12] IEC 61014 NOTE Harmonized as EN 61014:2003 (not modified).
[13] IEC 61164 NOTE Harmonized as EN 61164:2004 (not modified).
[14] ISO 10007 NOTE Harmonized as EN ISO 10007:1996 (not modified).
[16] IEC 60300-3-11 NOTE Harmonized as EN 60300-3-11:2009 (not modified).
[17] IEC 60300-3-12 NOTE Harmonized as EN 60300-3-12:2004 (not modified).
[22] IEC 60721 NOTE Harmonized in EN 60721 series (not modified).
IEC 60300-3-4 NOTE Harmonized as EN 60300-3-4:2008 (not modified).
IEC 60812 NOTE Harmonized as EN 60812:2006 (not modified).
IEC 61025 NOTE Harmonized as EN 61025:2007 (not modified).
IEC 61078 NOTE Harmonized as EN 61078:2006 (not modified).
IEC 61508-7 NOTE Harmonized as EN 61508-7:2001 (not modified).
IEC 61709 NOTE Harmonized as EN 61709:1998 (not modified).
IEC 62308 NOTE Harmonized as EN 62308:2006 (not modified).
ISO 13407 NOTE Harmonized as EN ISO 13407:1999 (not modified).
__________
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SIST EN 60300-3-15:2010
- 3 - EN 60300-3-15:2009
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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 When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD

applies.
Publication Year Title EN/HD Year
1) 2)
IEC 60300-1 - Dependability management - EN 60300-1 2003
Part 1: Dependability management systems
1) 2)
IEC 60300-2 - Dependability management - EN 60300-2 2004
Part 2: Guidelines for dependability
management
Undated reference.
Valid edition at date of issue.
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SIST EN 60300-3-15:2010
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SIST EN 60300-3-15:2010
IEC 60300-3-15
Edition 1.0 2009-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dependability management –
Part 3-15: Application guide – Engineering of system dependability
Gestion de la sûreté de fonctionnement –
Partie 3-15: Guide d’application – Ingénierie de la sûreté de fonctionnement des
systèmes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX
ICS 03.120.01 ISBN 2-8318-1048-4
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST EN 60300-3-15:2010
– 2 – 60300-3-15 © IEC:2009
CONTENTS

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

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

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

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

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

4 System dependability engineering and applications ..........................................................8

4.1 Overview of system dependability engineering ........................................................8

4.2 System dependability attributes and performance characteristics ............................9

5 Managing system dependability......................................................................................10

5.1 Dependability management ...................................................................................10

5.2 System dependability projects ...............................................................................10

5.3 Tailoring to meet project needs .............................................................................11

5.4 Dependability assurance .......................................................................................11

6 Realization of system dependability................................................................................11

6.1 Process for engineering dependability into systems...............................................11

6.1.1 Purpose of dependability process ..............................................................11

6.1.2 System life cycle and processes ................................................................11

6.1.3 Process applications through the system life cycle ....................................12

6.2 Achievement of system dependability....................................................................14

6.2.1 Purpose of system dependability achievements .........................................14

6.2.2 Criteria for system dependability achievements .........................................14

6.2.3 Methodology for system dependability achievements.................................15

6.2.4 Realization of system functions .................................................................16

6.2.5 Approaches to determine achievement of system dependability.................17

6.2.6 Objective evidence of achievements..........................................................18

6.3 Assessment of system dependability .....................................................................18

6.3.1 Purpose of system dependability assessments ..........................................18

6.3.2 Types of assessments ...............................................................................18

6.3.3 Methodology for system dependability assessments ..................................20

6.3.4 Assessment value and implications ...........................................................21

6.4 Measurement of system dependability...................................................................21

6.4.1 Purpose of system dependability measurements .......................................21

6.4.2 Classification of system dependability measurements................................22

6.4.3 Sources of measurements .........................................................................23

6.4.4 Enabling systems for dependability measurements ....................................23

6.4.5 Interpretation of dependability measurements............................................24

Annex A (informative) System life cycle processes and applications ....................................25

Annex B (informative) Methods and tools for system dependability development and

assurance.............................................................................................................................35

Annex C (informative) Guidance on system application environment....................................42

Annex D (informative) Checklists for System Dependability Engineering ..............................47

Bibliography..........................................................................................................................54

Figure 1 – An overview of a system life cycle........................................................................12

Figure 2 – An example of a process model ...........................................................................13

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SIST EN 60300-3-15:2010
60300-3-15 © IEC:2009 – 3 –

Figure A.1 – An overview of system life cycle processes.......................................................25

Figure C.1 – Environmental requirements definition process .................................................43

Figure C.2 – Mapping system application environments to exposures ...................................44

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SIST EN 60300-3-15:2010
– 4 – 60300-3-15 © IEC:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DEPENDABILITY MANAGEMENT –
Part 3-15: Application guide –
Engineering of system 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 should be clearly indicated

in the latter.

5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any

equipment declared to be in conformity with an IEC Publication.

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

7) No liability should 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 should not be held responsible for identifying any or all such patent rights.

International Standard IEC 60300-3-15 has been prepared by IEC technical committee 56:

Dependability.
The text of this standard is based on the following documents:
FDIS Report on voting
56/1315/FDIS 56/1321/RVD

Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

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

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SIST EN 60300-3-15:2010
60300-3-15 © IEC:2009 – 5 –

A list of all parts of the IEC 60300 series, under the general title Dependability management,

can be found on the IEC website.

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

the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in

the data related to the specific publication. At this date, the publication will be

• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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SIST EN 60300-3-15:2010
– 6 – 60300-3-15 © IEC:2009
INTRODUCTION

Systems are growing in complexity in today’s application environments. System dependability

has become an important performance attribute that affects the business strategies in system

acquisition and the cost-effectiveness in system ownership and operations. The overall

dependability of a system is the combined result of complex interactions of system elements,

application environments, human-machine interfaces, deployment of support services and

other influencing factors.

This part of IEC 60300 gives guidance on the engineering of the overall system to achieve its

dependability objectives. The engineering approach in this standard represents the

application of appropriate scientific knowledge and relevant technical disciplines for realizing

the required dependability for the system of interest.

The four main aspects for engineering dependability concerning systems are addressed in

terms of
– process,
– achievement,
– assessment, and
– measurement.

The engineering disciplines consist of technical processes that are applicable to the various

stages of the system life cycle. Specific technical processes described in this part of

IEC 60300 are supported by a sequence of relevant process activities to achieve the

objectives of each system life cycle stage.

This part of IEC 60300 is applicable to generic systems with interacting system functions

consisting of hardware, software and human elements to achieve system performance

objectives. In many cases a function can be realized by commercial off-the-shelf products. A

system can link to other systems to form a network. The boundaries separating a product from

a system, and a system from a network, can be distinguished by defining the application of

the entity. For example, a digital timer as a product can be used to synchronize the operation

of a computer; the computer as a system can be linked with other computers in a business

office for communications as a local area network. The application environment is applicable

to all kinds of systems. Examples of applicable systems include control systems for power

generation, fault-tolerant computing systems and systems for provision of maintenance

support services.

Guidance on dependability engineering is provided for generic systems. It does not classify

systems for special applications. The majority of systems in use are generally repairable

throughout their life cycle operation for economic reasons and practical applications. Non-

repairable systems such as communication satellites, remote sensing/monitoring equipment,

and one-shot devices are considered as application-specific systems. They require further

identification of specific application environment, operational conditions and additional

information on unique performance characteristics to achieve their mission success

objectives. Non-repairable subsystems and components are considered as throwaway items.

The selection of applicable processes for engineering dependability into a specific system is

carried out through the project tailoring and dependability management process.

This part of IEC 60300 forms part of the framework standards on system aspects of

dependability to support IEC 60300-1 and IEC 60300-2 on dependability management.

References are made to project management activities applicable to systems. They include

identification of dependability elements and tasks relevant to the system and guidelines for

dependability management reviews and tailoring of dependability projects.
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SIST EN 60300-3-15:2010
60300-3-15 © IEC:2009 – 7 –
DEPENDABILITY MANAGEMENT –
Part 3-15: Application guide –
Engineering of system dependability
1 Scope

This part of IEC 60300 provides guidance for an engineering system’s dependability and

describes a process for realization of system dependability through the system life cycle.

This standard is applicable to new system development and for enhancement of existing

systems involving interactions of system functions consisting of hardware, software and

human elements.

This standard also applies to providers of subsystems and suppliers of products that seek

system information and criteria for system integration. Methods and tools are provided for

system dependability assessment and verification of results for achievement of dependability

objectives.
2 Normative references

The following referenced documents are indispensable for the application 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 60300-1, Dependability management – Part 1: Dependability management systems

IEC 60300-2, Dependability management – Part 2: Guidelines for dependability management

3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
system

set of interrelated items considered as a whole for a defined purpose, separated from other

items

NOTE 1 A system is generally defined with the view of performing a definite function.

NOTE 2 The system is considered to be bound by an imaginary surface that intersects the links between the

system and the environment and the other external systems.

NOTE 3 External resources (i.e. outside the system boundary) may be required for the system to operate.

NOTE 4 A system structure may be hierarchical, e.g. system, subsystem, component, etc.

3.2
subsystem
system that is part of a more complex system
3.3
operating profile
complete set of tasks to achieve a specific system objective
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SIST EN 60300-3-15:2010
– 8 – 60300-3-15 © IEC:2009

NOTE 1 Configurations and operating scenarios form part of the mode of system operation.

NOTE 2 An operating profile is the sequence of required tasks to be performed by the system to achieve its

operational objective. The operating profile represents a specific operating scenario for the system in operation.

3.4
function

elementary operation performed by the system which, when combined with other elementary

operations (system functions), enables the system to perform a task
[IEC 61069-1 :1991, 2.2.5] [1]
3.5
element

combination of components that form the basic building block to perform a distinct function

NOTE 1 An element may comprise hardware, software, information and/or human components.

NOTE 2 For some systems, information and data are an important part of the system operations.

3.6
integrity

ability of a system to sustain its form, stability and robustness, and maintain its consistency in

performance and use
4 System dependability engineering and applications
4.1 Overview of system dependability engineering

Dependability is the ability of a system to perform as and when required to meet specific

objectives under given conditions of use. Dependability characteristics include availability and

its inherent or external influencing factors, such as: reliability, fault tolerance, recoverability,

The dependability of a
integrity, security, maintainability, durability and maintenance support.

system infers that the system is trustworthy and capable of performing the desirable service

upon demand to satisfy user needs. The system objective, structure, properties, and

influencing conditions affecting system dependability performance are described in IEC 62347

[2] which provides guidance for determination of relevant system functions for specifying

system dependability.
There are four main aspects for engineering dependability into systems:
a) dependability process – establishes the technical processes for engineering

dependability into systems. The process consists of a sequence of activities implemented

at each respective life cycle stage to achieve specific dependability objectives in system

performance. The dependability process shall be fully integrated into the design and

management processes;

b) dependability achievement – implementation of the effective engineering effort and

knowledge experience applied at appropriate system life cycle stages. The aim is for

progressive accomplishment of dependability objectives of the constituent system

functions suitable for subsystem realization and system integration (reliability growth);

c) dependability assessment – evaluates the dependability attributes and determines their

effectiveness when implemented into systems. The process identifies the specific
dependability attributes to meet project needs and provides the methodology and
rationale on how these attributes can be determined;

d) dependability measurement – quantifies the dependability attributes for contracting,

specification and assessment purposes. The process is to assign a quantitative value or

number to designate a target entity representing a specific dependability characteristic.

___________
Figures in square brackets refer to the bibliography.
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SIST EN 60300-3-15:2010
60300-3-15 © IEC:2009 – 9 –

The aim is to express a statement of intent in quantifiable terms to facilitate mutual

understanding of the issue involved and to serve as basis for negotiation in reaching

agreements.
4.2 System dependability attributes and performance characteristics

System dependability attributes are those specific dependability related features and time-

dependent performance characteristics inherent in the system by design and construction.

Some features, such as system performance characteristics can be quantified and measured.

Other dependability features which are not quantifiable may present certain value or useful

information pertinent to those attributes. These non-quantifiable features can be described in

qualitative terms to establish its value for subjective dependability assessment. Both

quantifiable and non-quantifiable features are important to describe the system dependability

attributes. Examples of non-quantifiable features include product brand value, user friendly

operation, and informative instructions. Examples of quantifiable performance characteristics

include uptime duration, downtime frequency, mean-time-between-failures, and time for

restoration from a degraded state back to normal system performance.
The main attributes of system dependability are as follows:

a) availability: the ability of the system to be in a state to perform a required function when

a demand is placed upon the system. Availability performance is characterized in terms of

measures such as percentage uptime for the duration of system performance operation

upon demand; outage frequency and downtime duration;

b) reliability: the ability of the system to perform a required function for a given period of

time under given conditions of use. Reliability performance is characterized in terms of

measurements such as mean-time-between-failures and failure-free duration;

c) maintainability: the ability of the system to be restored to a state in which it can provide

a required function following a failure, or retained in such an up-state, under given

conditions of use and maintenance. Maintainability performance is characterized in terms

of measurements such as mean-time-to-restore and recovery time;

d) maintenance support: ability of an organization to provide, when required, the resources

required to maintain a system, under given conditions. Maintenance support performance

is characterized in terms of measures such as utilization of maintenance resources,

training needs, enabling tools and facilities, logistics delay time and turn-around time for

spares provisioning.

There are other attributes related to dependability for specific system applications. They

include but are not limited to:

e) recoverability: ability of a system to be restored to a state in which it can perform a

required function following a failure without repair of hardware or software. It is

characterized in terms of measurements such as mean-time-to-recover;

f) testability: ability of a system to be tested at designated maintenance levels for

replace/repair action to determine fault coverage. It is characterized in terms of

measurements such as percentage of test coverage;

g) service accessibility: ability of a service to be obtained within specified tolerances and

other given conditions when requested by the user. It is characterized in terms of

measurements such as probability of access to a service;

h) service retainability: ability of a service, once obtained, to continue to be provided under

given conditions for a requested duration. It is characterized i
...

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